diff --git a/scripts/daily-seed/constants.js b/scripts/daily-seed/constants.js
index edb80ba2cf7e..390c6c622d72 100644
--- a/scripts/daily-seed/constants.js
+++ b/scripts/daily-seed/constants.js
@@ -34,6 +34,9 @@ export const EDIT_OPTIONS = /** @type {const} */ ([
   "biome",
   "luck",
   "forced waves",
+  "trainer manipulation",
+  "challenges",
+  "mystery encounters",
   "starting money",
   "seed",
   "edit",
@@ -49,6 +52,8 @@ export const BOSS_OPTIONS = /** @type {const} */ ([
   "nature",
   "ability",
   "passive",
+  "segments",
+  "catchable",
   "finish",
 ]);
 
@@ -58,7 +63,8 @@ export const STARTER_OPTIONS = /** @type {const} */ ([
   "variant",
   "moveset",
   "nature",
-  "abilityIndex",
+  "ability",
+  "passive",
   "finish",
 ]);
 
diff --git a/scripts/daily-seed/main.js b/scripts/daily-seed/main.js
index aed5fd48fcaa..5e09a1b32bcf 100644
--- a/scripts/daily-seed/main.js
+++ b/scripts/daily-seed/main.js
@@ -19,7 +19,17 @@ import { toTitleCase } from "../helpers/casing.js";
 import { promptOverwrite, writeFileSafe } from "../helpers/file.js";
 import { EDIT_OPTIONS } from "./constants.js";
 import { promptBoss } from "./prompts/boss.js";
-import { promptBiome, promptEdit, promptForcedWaves, promptLuck, promptMoney, promptSeed } from "./prompts/general.js";
+import {
+  promptBiome,
+  promptChallenges,
+  promptEdit,
+  promptForcedWaves,
+  promptLuck,
+  promptMoney,
+  promptMysteryEncounters,
+  promptSeed,
+  promptTrainerManipulation,
+} from "./prompts/general.js";
 import { promptStarters } from "./prompts/starter.js";
 
 /**
@@ -33,7 +43,8 @@ const rootDir = join(import.meta.dirname, "..", "..");
 /**
  * @import {BossConfig} from "./prompts/boss.js"
  * @import {StarterConfig} from "./prompts/starter.js"
- * @import {ForcedWaveConfig} from "./prompts/general.js"
+ * @import {ForcedWaveConfig, DailyTrainerManipulation, DailyEventChallenge} from "./prompts/general.js"
+ * @import {DailyEventMysteryEncounter} from "./prompts/general.js"
  */
 
 /**
@@ -48,6 +59,9 @@ const rootDir = join(import.meta.dirname, "..", "..");
  *   biome?: number,
  *   luck?: number,
  *   forcedWaves?: ForcedWaveConfig[],
+ *   trainerManipulations?: DailyTrainerManipulation[],
+ *   challenges?: DailyEventChallenge[],
+ *   mysteryEncounters?: DailyEventMysteryEncounter[],
  *   startingMoney?: number,
  *   seed: string
  * }}
@@ -58,6 +72,8 @@ const customSeedConfig = {
   biome: undefined,
   luck: undefined,
   forcedWaves: undefined,
+  trainerManipulations: undefined,
+  challenges: undefined,
   startingMoney: undefined,
   seed: "",
 };
@@ -137,6 +153,15 @@ async function handleAnswer(answer) {
     case "forced waves":
       customSeedConfig.forcedWaves = await promptForcedWaves();
       break;
+    case "trainer manipulation":
+      customSeedConfig.trainerManipulations = await promptTrainerManipulation();
+      break;
+    case "challenges":
+      customSeedConfig.challenges = await promptChallenges();
+      break;
+    case "mystery encounters":
+      customSeedConfig.mysteryEncounters = await promptMysteryEncounters();
+      break;
     case "starting money":
       customSeedConfig.startingMoney = await promptMoney();
       break;
diff --git a/scripts/daily-seed/prompts/boss.js b/scripts/daily-seed/prompts/boss.js
index c6da6e9c4e6d..c1f9283c2905 100644
--- a/scripts/daily-seed/prompts/boss.js
+++ b/scripts/daily-seed/prompts/boss.js
@@ -5,7 +5,7 @@
  * SPDX-License-Identifier: AGPL-3.0-only
  */
 
-import { select } from "@inquirer/prompts";
+import { confirm, select } from "@inquirer/prompts";
 import chalk from "chalk";
 import { toCamelCase, toTitleCase } from "../../helpers/casing.js";
 import { BOSS_OPTIONS } from "../constants.js";
@@ -14,6 +14,7 @@ import {
   promptFormIndex,
   promptMoveset,
   promptNature,
+  promptSegments,
   promptSpeciesId,
   promptVariant,
 } from "./pokemon.js";
@@ -28,7 +29,9 @@ import {
  *   moveset?: number[],
  *   nature?: number,
  *   ability?: number,
- *   passive?: number
+ *   passive?: number,
+ *   segments?: number,
+ *   catchable?: boolean,
  * }} BossConfig - The config for a single boss pokemon.
  *
  */
@@ -45,6 +48,8 @@ let bossConfig = {
   nature: undefined,
   ability: undefined,
   passive: undefined,
+  segments: undefined,
+  catchable: undefined,
 };
 
 /**
@@ -99,6 +104,15 @@ async function promptBossOptions() {
     case "passive":
       bossConfig.passive = await promptAbility(true);
       break;
+    case "segments":
+      bossConfig.segments = await promptSegments();
+      break;
+    case "catchable":
+      bossConfig.catchable = await confirm({
+        message: "Should the boss be catchable?",
+        default: false,
+      });
+      break;
     case "finish":
       return bossConfig;
   }
diff --git a/scripts/daily-seed/prompts/general.js b/scripts/daily-seed/prompts/general.js
index a866a20f4f82..e9195e919373 100644
--- a/scripts/daily-seed/prompts/general.js
+++ b/scripts/daily-seed/prompts/general.js
@@ -10,6 +10,8 @@ import { Ajv } from "ajv";
 import chalk from "chalk";
 import customDailyRunSchema from "../../../src/data/daily-seed/schema.json" with { type: "json" };
 import { BIOMES } from "../../enums/biomes.js";
+import { CHALLENGES } from "../../enums/challenges.js";
+import { MYSTERY_ENCOUNTERS } from "../../enums/mystery-encounters.js";
 import { toTitleCase, toUpperSnakeCase } from "../../helpers/casing.js";
 import { BIOME_POOL_TIERS } from "../constants.js";
 import { promptSpeciesId } from "./pokemon.js";
@@ -26,6 +28,27 @@ import { promptSpeciesId } from "./pokemon.js";
  * }} ForcedWaveConfig
  */
 
+/**
+ * @typedef {{
+ *   waveIndex: number,
+ *   isTrainer: boolean,
+ * }} DailyTrainerManipulation
+ */
+
+/**
+ * @typedef {{
+ *   id: number,
+ *   value: number,
+ * }} DailyEventChallenge
+ */
+
+/**
+ * @typedef {{
+ *  waveIndex: number,
+ *  type: number,
+ * }} DailyEventMysteryEncounter
+ */
+
 const ajv = new Ajv({
   allErrors: true,
 });
@@ -196,3 +219,135 @@ export async function promptForcedWaves() {
   }
   return forcedWaves;
 }
+
+/**
+ * Prompt the user to enter a list of trainer manipulations.
+ * @returns {Promise<DailyTrainerManipulation[] | undefined>} A Promise that resolves with the list of trainer manipulations.
+ */
+export async function promptTrainerManipulation() {
+  /** @type {DailyTrainerManipulation[]} */
+  const trainerManipulations = [];
+
+  async function addTrainerManipulation() {
+    const waveIndex = await number({
+      message: "Please enter the wave to manipulate.\nPressing ENTER will end the prompt early.",
+      min: 1,
+      max: 49,
+      validate: value => {
+        if (trainerManipulations.some(wave => wave.waveIndex === value)) {
+          return chalk.red.bold("Wave already manipulated!");
+        }
+        return true;
+      },
+    });
+    if (!waveIndex) {
+      return;
+    }
+
+    const isTrainer = await confirm({
+      message: "Should the wave be a trainer?",
+      default: false,
+    });
+
+    trainerManipulations.push({ waveIndex, isTrainer });
+
+    await addTrainerManipulation();
+  }
+
+  await addTrainerManipulation();
+  if (trainerManipulations.length === 0) {
+    return;
+  }
+  return trainerManipulations;
+}
+
+/**
+ * Prompt the user to enter a list of challenges.
+ * @returns {Promise<DailyEventChallenge[] | undefined>} A Promise that resolves with the list of challenges.
+ */
+export async function promptChallenges() {
+  /** @type {DailyEventChallenge[]} */
+  const challenges = [];
+  const challengeNames = Object.keys(CHALLENGES).map(toTitleCase);
+  challengeNames.unshift("Finish");
+
+  async function addChallenge() {
+    const challenge = await search({
+      message: "Please enter the challenge to add.\nPressing ENTER will end the prompt early.",
+      source: term => {
+        if (!term) {
+          return challengeNames;
+        }
+        return challengeNames.filter(id => id.toLowerCase().includes(term.toLowerCase()));
+      },
+    });
+    if (challenge === "Finish") {
+      return;
+    }
+
+    const value = await number({
+      message: `Please enter the value for ${challenge}. This is NOT validted atm.`,
+      min: 0,
+      required: true,
+    });
+
+    const challengeId = CHALLENGES[/** @type {keyof typeof CHALLENGES} */ (toUpperSnakeCase(challenge))];
+    challenges.push({ id: challengeId, value });
+    challengeNames.splice(challengeNames.indexOf(challenge), 1);
+    await addChallenge();
+  }
+  await addChallenge();
+
+  if (challenges.length === 0) {
+    return;
+  }
+  return challenges;
+}
+
+/**
+ * Prompt the user to enter a list of mystery encounters.
+ * @returns {Promise<DailyEventMysteryEncounter[] | undefined>} A Promise that resolves with the list of mystery encounters.
+ */
+export async function promptMysteryEncounters() {
+  /** @type {DailyEventMysteryEncounter[]} */
+  const mysteryEncounters = [];
+
+  async function addMysteryEncounter() {
+    const waveIndex = await number({
+      message: "Please enter the wave to force a mystery encounter.\nPressing ENTER will end the prompt early.",
+      min: 1,
+      max: 49,
+      validate: value => {
+        if (mysteryEncounters.some(wave => wave.waveIndex === value)) {
+          return chalk.red.bold("Wave already has a mystery encounter!");
+        }
+        return true;
+      },
+    });
+    if (!waveIndex) {
+      return;
+    }
+
+    const type = await search({
+      message: "Please select the mystery encounter to force.",
+      source: term => {
+        if (!term) {
+          return Object.keys(MYSTERY_ENCOUNTERS).map(toTitleCase);
+        }
+        return Object.keys(MYSTERY_ENCOUNTERS)
+          .map(toTitleCase)
+          .filter(id => id.toLowerCase().includes(term.toLowerCase()));
+      },
+    });
+
+    const typeId = MYSTERY_ENCOUNTERS[/** @type {keyof typeof MYSTERY_ENCOUNTERS} */ (toUpperSnakeCase(type))];
+    mysteryEncounters.push({ waveIndex, type: typeId });
+    await addMysteryEncounter();
+  }
+
+  await addMysteryEncounter();
+  if (mysteryEncounters.length === 0) {
+    return;
+  }
+  return mysteryEncounters;
+}
diff --git a/scripts/daily-seed/prompts/pokemon.js b/scripts/daily-seed/prompts/pokemon.js
index 1ffa72cd551b..4d87f943523f 100644
--- a/scripts/daily-seed/prompts/pokemon.js
+++ b/scripts/daily-seed/prompts/pokemon.js
@@ -18,7 +18,6 @@ import { toTitleCase, toUpperSnakeCase } from "../../helpers/casing.js";
 
 /**
  * Prompt the user to enter a speciesId.
- * @see {@linkcode SPECIES_IDS} for a list of valid `SpeciesId`s.
  * @returns {Promise<number>} A Promise that resolves with the chosen `SpeciesId`.
  */
 export async function promptSpeciesId() {
@@ -131,8 +130,6 @@ export async function promptMoveset() {
  * Prompt the user to enter an ability.
  * @param {boolean} [passive=false] (Default `false`) Whether to prompt for a passive ability.
  * @returns {Promise<number>} A Promise that resolves with the chosen ability.
- * @remarks
- * This is boss only for now, since the option for setting any ability is not yet implemented.
  */
 export async function promptAbility(passive = false) {
   const abilityName = await search({
@@ -150,16 +147,14 @@ export async function promptAbility(passive = false) {
 }
 
 /**
- * Prompt the user to enter an ability index.
- * @returns {Promise<number>} A Promise that resolves with the chosen ability index.
- * @remarks This is starter only for now.
+ * Prompt the user to enter the number of segments for the boss fight.
+ * @returns {Promise<number>} A Promise that resolves with the chosen number of segments.
  */
-// TODO: Validate the ability index & list the actual ability names based on main repo data
-export async function promptAbilityIndex() {
+export async function promptSegments() {
   return await number({
-    message: `Please enter the starter's ability index.`,
-    min: 0,
-    max: 2,
+    message: "Please enter the number of segments for the boss fight.",
+    min: 1,
+    default: 5,
     required: true,
   });
 }
diff --git a/scripts/daily-seed/prompts/starter.js b/scripts/daily-seed/prompts/starter.js
index ea14cc8c7baf..6a8fef2456c1 100644
--- a/scripts/daily-seed/prompts/starter.js
+++ b/scripts/daily-seed/prompts/starter.js
@@ -9,7 +9,7 @@ import { number, select } from "@inquirer/prompts";
 import { toCamelCase, toTitleCase } from "../../helpers/casing.js";
 import { STARTER_OPTIONS } from "../constants.js";
 import {
-  promptAbilityIndex,
+  promptAbility,
   promptFormIndex,
   promptMoveset,
   promptNature,
@@ -26,7 +26,8 @@ import {
  *   variant?: Variant,
  *   moveset?: number[],
  *   nature?: number,
- *   abilityIndex?: number,
+ *   ability?: number,
+ *   passive?: number
  * }} StarterConfig
  */
 
@@ -99,8 +100,11 @@ async function promptStarterOptions(starterConfig) {
     case "nature":
       starterConfig.nature = await promptNature();
       break;
-    case "abilityIndex":
-      starterConfig.abilityIndex = await promptAbilityIndex();
+    case "ability":
+      starterConfig.ability = await promptAbility();
+      break;
+    case "passive":
+      starterConfig.passive = await promptAbility(true);
       break;
     case "finish":
       // Re-add all used options for next starter
diff --git a/scripts/enums/challenges.js b/scripts/enums/challenges.js
new file mode 100644
index 000000000000..713ea546930e
--- /dev/null
+++ b/scripts/enums/challenges.js
@@ -0,0 +1,23 @@
+/*
+ * SPDX-FileCopyrightText: 2026 Pagefault Games
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+/**
+ * A mapping of challenge names to their corresponding IDs.
+ * @enum {number}
+ */
+export const CHALLENGES = {
+  SINGLE_GENERATION: 0,
+  SINGLE_TYPE: 1,
+  LOWER_MAX_STARTER_COST: 2,
+  LOWER_STARTER_POINTS: 3,
+  FRESH_START: 4,
+  INVERSE_BATTLE: 5,
+  FLIP_STAT: 6,
+  LIMITED_CATCH: 7,
+  LIMITED_SUPPORT: 8,
+  HARDCORE: 9,
+  PASSIVES: 10,
+};
diff --git a/scripts/enums/mystery-encounters.js b/scripts/enums/mystery-encounters.js
new file mode 100644
index 000000000000..263b4e40a802
--- /dev/null
+++ b/scripts/enums/mystery-encounters.js
@@ -0,0 +1,43 @@
+/*
+ * SPDX-FileCopyrightText: 2026 Pagefault Games
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+/**
+ * A mapping of mystery encounter names to their corresponding IDs.
+ * @enum {number}
+ */
+export const MYSTERY_ENCOUNTERS = {
+  MYSTERIOUS_CHALLENGERS: 0,
+  MYSTERIOUS_CHEST: 1,
+  DARK_DEAL: 2,
+  FIGHT_OR_FLIGHT: 3,
+  SLUMBERING_SNORLAX: 4,
+  TRAINING_SESSION: 5,
+  DEPARTMENT_STORE_SALE: 6,
+  SHADY_VITAMIN_DEALER: 7,
+  FIELD_TRIP: 8,
+  SAFARI_ZONE: 9,
+  LOST_AT_SEA: 10,
+  FIERY_FALLOUT: 11,
+  THE_STRONG_STUFF: 12,
+  THE_POKEMON_SALESMAN: 13,
+  AN_OFFER_YOU_CANT_REFUSE: 14,
+  DELIBIRDY: 15,
+  ABSOLUTE_AVARICE: 16,
+  A_TRAINERS_TEST: 17,
+  TRASH_TO_TREASURE: 18,
+  BERRIES_ABOUND: 19,
+  CLOWNING_AROUND: 20,
+  PART_TIMER: 21,
+  DANCING_LESSONS: 22,
+  WEIRD_DREAM: 23,
+  THE_WINSTRATE_CHALLENGE: 24,
+  TELEPORTING_HIJINKS: 25,
+  BUG_TYPE_SUPERFAN: 26,
+  FUN_AND_GAMES: 27,
+  UNCOMMON_BREED: 28,
+  GLOBAL_TRADE_SYSTEM: 29,
+  THE_EXPERT_POKEMON_BREEDER: 30,
+};
diff --git a/src/@types/daily-run.ts b/src/@types/daily-run.ts
index 90db4055e7ce..7148572727d3 100644
--- a/src/@types/daily-run.ts
+++ b/src/@types/daily-run.ts
@@ -1,6 +1,8 @@
 import type { AbilityId } from "#enums/ability-id";
 import type { BiomeId } from "#enums/biome-id";
 import type { BiomePoolTier } from "#enums/biome-pool-tier";
+import type { Challenges } from "#enums/challenges";
+import type { MysteryEncounterType } from "#enums/mystery-encounter-type";
 import type { Nature } from "#enums/nature";
 import type { SpeciesId } from "#enums/species-id";
 import type { Variant } from "#sprites/variant";
@@ -19,7 +21,8 @@ export interface DailySeedStarter {
   variant?: Variant | undefined;
   moveset?: StarterMoveset | undefined;
   nature?: Nature | undefined;
-  abilityIndex?: number | undefined;
+  ability?: AbilityId | undefined;
+  passive?: AbilityId | undefined;
 }
 
 type DailySeedStarterTuple = TupleRange<1, 6, DailySeedStarter>;
@@ -38,6 +41,8 @@ export interface DailySeedBoss {
   nature?: Nature | undefined;
   ability?: AbilityId | undefined;
   passive?: AbilityId | undefined;
+  segments?: number | undefined;
+  catchable?: boolean | undefined;
 }
 
 /**
@@ -49,6 +54,9 @@ export interface DailySeedBoss {
  *   speciesId: SpeciesId.MEW,
  * };
  * ```
+ * @privateRemarks
+ * When updating this interface, also update:
+ * - `src/data/daily-seed/schema.json`
  */
 export type DailyForcedWave =
   | {
@@ -64,6 +72,27 @@ export type DailyForcedWave =
       hiddenAbility?: boolean | undefined;
     };
 
+/**
+ * Configuration to manipulate on what waves a trainer spawns for a custom seed.
+ * @privateRemarks
+ * When updating this interface, also update:
+ * - `src/data/daily-seed/schema.json`
+ */
+export interface DailyTrainerManipulation {
+  waveIndex: number;
+  isTrainer: boolean;
+}
+
+export interface DailyEventChallenge {
+  id: Challenges;
+  value: number;
+}
+
+export interface DailyEventMysteryEncounter {
+  waveIndex: number;
+  type: MysteryEncounterType;
+}
+
 /**
  * Configuration for a custom daily run seed.
  * @privateRemarks
@@ -77,6 +106,9 @@ export interface CustomDailyRunConfig {
   luck?: number;
   startingMoney?: number;
   forcedWaves?: DailyForcedWave[];
+  trainerManipulations?: DailyTrainerManipulation[];
+  challenges?: DailyEventChallenge[];
+  mysteryEncounters?: DailyEventMysteryEncounter[];
   /** The actual seed used for the daily run. */
   seed: string;
 }
@@ -88,5 +120,8 @@ export interface SerializedDailyRunConfig {
   boss?: DailySeedBoss | undefined;
   luck?: number | undefined;
   forcedWaves?: DailyForcedWave[] | undefined;
+  trainerManipulations?: DailyTrainerManipulation[] | undefined;
+  challenges?: DailyEventChallenge[] | undefined;
+  mysteryEncounters?: DailyEventMysteryEncounter[] | undefined;
   seed: string;
 }
diff --git a/src/@types/events.ts b/src/@types/events.ts
index 6932dfa77e19..ef1ce0212259 100644
--- a/src/@types/events.ts
+++ b/src/@types/events.ts
@@ -1,5 +1,4 @@
 import type { BiomeId } from "#enums/biome-id";
-import type { Challenges } from "#enums/challenges";
 import type { EventType } from "#enums/event-type";
 import type { ClassicFixedBossWaves } from "#enums/fixed-boss-waves";
 import type { MysteryEncounterTier } from "#enums/mystery-encounter-tier";
@@ -38,12 +37,23 @@ export interface EventWaveReward {
 }
 
 export type EventMusicReplacement = readonly [string, string];
+export type EventSpriteReplacement = readonly [string, string];
 
-export interface EventChallenge {
-  readonly challenge: Challenges;
-  readonly value: number;
+export interface EventSpriteOptions {
+  /**
+   * An Array of tuples [source, target] for replacing pokemon sprites during events.
+   * Format for both source and target is "speciesId[/formIndex]", where formIndex is optional and defaults to 0 if not provided.
+   */
+  readonly replacements: readonly EventSpriteReplacement[];
+  /**
+   * If true, any species not explicitly listed in the replacements array will be replaced with a random species.
+   * @defaultValue false
+   */
+  readonly fillRandom?: boolean;
 }
 
+export type EventTextReplacement = readonly [string, string];
+
 export type EventWeatherPools = Readonly<Partial<Record<BiomeId, WeatherPool>>>;
 export type EventTerrainPools = Readonly<Partial<Record<BiomeId, TerrainPool>>>;
 
@@ -67,6 +77,7 @@ export interface TimedEvent extends EventBanner {
   readonly classicWaveRewards?: readonly EventWaveReward[]; // Rival battle rewards
   readonly trainerShinyChance?: number; // Odds over 65536 of trainer mon generating as shiny
   readonly music?: readonly EventMusicReplacement[];
-  readonly dailyRunChallenges?: readonly EventChallenge[];
+  readonly sprites?: EventSpriteOptions;
+  readonly textReplacements?: readonly EventTextReplacement[];
   readonly dailyRunStartingItems?: readonly ModifierTypeKeys[];
 }
diff --git a/src/battle-scene.ts b/src/battle-scene.ts
index 63a4ef7f0e67..57161e74c3f7 100644
--- a/src/battle-scene.ts
+++ b/src/battle-scene.ts
@@ -27,6 +27,7 @@ import { STARTING_WAVE } from "#balance/misc";
 import { pokemonPrevolutions } from "#balance/pokemon-evolutions";
 import { FRIENDSHIP_GAIN_FROM_BATTLE } from "#balance/starters";
 import { initCommonAnims, initMoveAnim, loadCommonAnimAssets, loadMoveAnimAssets } from "#data/battle-anims";
+import { getDailyMysteryEncounter } from "#data/daily-seed/daily-run";
 import { allMoves, allSpecies, biomeDepths, modifierTypes } from "#data/data-lists";
 import { battleSpecDialogue } from "#data/dialogue";
 import type { SpeciesFormChangeTrigger } from "#data/form-change-triggers";
@@ -1875,6 +1876,9 @@ export class BattleScene extends SceneBase {
     }
 
     if (this.gameMode.isDaily && this.gameMode.isWaveFinal(waveIndex)) {
+      if (this.gameMode.dailyConfig?.boss?.segments != null) {
+        return this.gameMode.dailyConfig.boss.segments;
+      }
       return 5;
     }
 
@@ -3614,6 +3618,9 @@ export class BattleScene extends SceneBase {
    * @returns Whether a Mystery Encounter should be generated.
    */
   private isWaveMysteryEncounter(battleType: BattleType, waveIndex: number): boolean {
+    if (getDailyMysteryEncounter(waveIndex) != null) {
+      return true;
+    }
     if (!this.isMysteryEncounterValidForWave(battleType, waveIndex)) {
       return false;
     }
@@ -3691,6 +3698,8 @@ export class BattleScene extends SceneBase {
     } else if (canBypass) {
       encounter = allMysteryEncounters[encounterType ?? -1];
       return encounter;
+    } else if (getDailyMysteryEncounter(this.currentBattle.waveIndex) != null) {
+      encounter = allMysteryEncounters[getDailyMysteryEncounter(this.currentBattle.waveIndex)!];
     } else {
       encounter = encounterType != null ? allMysteryEncounters[encounterType] : null;
     }
diff --git a/src/data/balance/timed-events.ts b/src/data/balance/timed-events.ts
index 7cec881b2440..56a8b887fab0 100644
--- a/src/data/balance/timed-events.ts
+++ b/src/data/balance/timed-events.ts
@@ -1,5 +1,4 @@
 import { BiomeId } from "#enums/biome-id";
-import { Challenges } from "#enums/challenges";
 import { EventType } from "#enums/event-type";
 import { MysteryEncounterTier } from "#enums/mystery-encounter-tier";
 import { MysteryEncounterType } from "#enums/mystery-encounter-type";
@@ -337,12 +336,13 @@ export const timedEvents: readonly TimedEvent[] = [
       ["title", "title_afd"],
       ["battle_rival_3", "battle_rival_3_afd"],
     ],
-    dailyRunChallenges: [
-      {
-        challenge: Challenges.INVERSE_BATTLE,
-        value: 1,
-      },
-    ],
+    // This has been moved to custom seeds. Keeping this here to keep track of what the event did.
+    // dailyRunChallenges: [
+    //   {
+    //     challenge: Challenges.INVERSE_BATTLE,
+    //     value: 1,
+    //   },
+    // ],
   },
   {
     name: "Shining Spring",
diff --git a/src/data/daily-seed/daily-run.ts b/src/data/daily-seed/daily-run.ts
index f1d8dc788e1f..d77cc17289ab 100644
--- a/src/data/daily-seed/daily-run.ts
+++ b/src/data/daily-seed/daily-run.ts
@@ -5,8 +5,10 @@ import { speciesStarterCosts } from "#balance/starters";
 import type { PokemonSpecies } from "#data/pokemon-species";
 import { BiomeId } from "#enums/biome-id";
 import type { BiomePoolTier } from "#enums/biome-pool-tier";
+import { Challenges } from "#enums/challenges";
 import { EvoLevelThresholdKind } from "#enums/evo-level-threshold-kind";
 import { MoveId } from "#enums/move-id";
+import { MysteryEncounterType } from "#enums/mystery-encounter-type";
 import { PartyMemberStrength } from "#enums/party-member-strength";
 import type { SpeciesId } from "#enums/species-id";
 import type { DailySeedBoss } from "#types/daily-run";
@@ -224,6 +226,11 @@ export function getDailyForcedWaveSpecies(waveIndex: number): PokemonSpecies | n
   return getPokemonSpecies(forcedWave.speciesId);
 }
 
+/**
+ * Get the biome pool tier for a forced wave for custom daily run.
+ * @param waveIndex - The wave index to check
+ * @returns The {@linkcode BiomePoolTier} to use, or `null` if there is no forced wave for the given index.
+ */
 export function getDailyForcedWaveBiomePoolTier(waveIndex: number): BiomePoolTier | null {
   if (!isDailyEventSeed()) {
     return null;
@@ -242,6 +249,11 @@ export function getDailyForcedWaveBiomePoolTier(waveIndex: number): BiomePoolTie
   return forcedWave.tier;
 }
 
+/**
+ * Check if the current wave should have the hidden ability in a custom daily run.
+ * @param waveIndex - The wave index to check
+ * @returns Whether the wave should have the hidden ability.
+ */
 export function isDailyForcedWaveHiddenAbility(): boolean {
   if (!isDailyEventSeed()) {
     return false;
@@ -262,6 +274,67 @@ export function isDailyForcedWaveHiddenAbility(): boolean {
   return forcedWave.hiddenAbility ?? false;
 }
 
+/**
+ * Check if the current wave should be a trainer battle in a custom daily run.
+ * @param waveIndex - The wave index to check
+ * @returns The {@linkcode DailyTrainerManipulation} to use, or `null` if there is no forced wave for the given index.
+ */
+export function getDailyTrainerManipulation(waveIndex: number): boolean | null {
+  if (!isDailyEventSeed()) {
+    return null;
+  }
+  const trainerManipulation = globalScene.gameMode.dailyConfig?.trainerManipulations?.find(
+    w => w.waveIndex === waveIndex,
+  );
+  if (trainerManipulation == null) {
+    return null;
+  }
+
+  return trainerManipulation.isTrainer;
+}
+
+/**
+ * Starts the challenges for a custom daily run.
+ */
+export function startDailyEventChallenges(): void {
+  if (!isDailyEventSeed()) {
+    return;
+  }
+
+  const { dailyConfig } = globalScene.gameMode;
+
+  for (const dailyChallenge of dailyConfig?.challenges ?? []) {
+    if (!getEnumValues(Challenges).includes(dailyChallenge.id)) {
+      console.warn("Invalid challenge ID used for custom daily run seed:", dailyChallenge.id);
+      continue;
+    }
+    globalScene.gameMode.setChallengeValue(dailyChallenge.id, dailyChallenge.value);
+  }
+}
+
+/**
+ * Get the {@linkcode MysteryEncounterType} for a custom daily run.
+ * @param waveIndex - The wave index to check
+ * @returns The {@linkcode MysteryEncounterType} to use, or `null` if there is no forced wave for the given index.
+ */
+export function getDailyMysteryEncounter(waveIndex: number): MysteryEncounterType | null {
+  if (!isDailyEventSeed()) {
+    return null;
+  }
+
+  const mysteryEncounter = globalScene.gameMode.dailyConfig?.mysteryEncounters?.find(w => w.waveIndex === waveIndex);
+  if (mysteryEncounter == null) {
+    return null;
+  }
+
+  if (!getEnumValues(MysteryEncounterType).includes(mysteryEncounter.type)) {
+    console.warn("Invalid mystery encounter type used for custom daily run seed:", mysteryEncounter.type);
+    return null;
+  }
+
+  return mysteryEncounter.type;
+}
+
 /**
  * Sets a custom starting biome for the daily run if specified in the config.
  * @see {@linkcode CustomDailyRunConfig}
diff --git a/src/data/daily-seed/daily-seed-utils.ts b/src/data/daily-seed/daily-seed-utils.ts
index 104839c47ee0..fabfa5167559 100644
--- a/src/data/daily-seed/daily-seed-utils.ts
+++ b/src/data/daily-seed/daily-seed-utils.ts
@@ -67,12 +67,16 @@ export function getSerializedDailyRunConfig(): SerializedDailyRunConfig | undefi
     return;
   }
 
-  const { seed, boss, luck, forcedWaves } = globalScene.gameMode.dailyConfig;
+  const { seed, boss, luck, forcedWaves, trainerManipulations, challenges, mysteryEncounters } =
+    globalScene.gameMode.dailyConfig;
   return {
     seed,
     boss,
     luck,
     forcedWaves,
+    trainerManipulations,
+    challenges,
+    mysteryEncounters,
   } satisfies SerializedDailyRunConfig;
 }
 
@@ -114,9 +118,15 @@ export function validateDailyStarterConfig(config: DailySeedStarter): DailySeedS
     config.nature = undefined;
   }
 
-  if (config.abilityIndex != null && !isBetween(config.abilityIndex, 0, 2)) {
-    console.warn("Invalid ability index used for custom daily run seed starter:", config.abilityIndex);
-    config.abilityIndex = undefined;
+  const abilityIds = getEnumValues(AbilityId);
+  if (config.ability != null && !abilityIds.includes(config.ability)) {
+    console.warn("Invalid ability used for custom daily run seed starter:", config.ability);
+    config.ability = undefined;
+  }
+
+  if (config.passive != null && !abilityIds.includes(config.passive)) {
+    console.warn("Invalid passive used for custom daily run seed starter:", config.passive);
+    config.passive = undefined;
   }
 
   return config;
@@ -178,6 +188,11 @@ export function validateDailyBossConfig(config: DailySeedBoss): DailySeedBoss |
     config.passive = undefined;
   }
 
+  if (config.segments != null && config.segments < 1) {
+    console.warn("Invalid number of segments used for custom daily run seed boss:", config.segments);
+    config.segments = undefined;
+  }
+
   return config;
 }
 
@@ -193,7 +208,7 @@ export function getDailyRunStarter(species: PokemonSpecies, config?: DailySeedSt
   const pokemon = globalScene.addPlayerPokemon(
     species,
     startingLevel,
-    config?.abilityIndex,
+    undefined,
     config?.formIndex,
     undefined,
     isShiny,
diff --git a/src/data/daily-seed/schema.json b/src/data/daily-seed/schema.json
index 0e8687610707..cb6beb198fa2 100644
--- a/src/data/daily-seed/schema.json
+++ b/src/data/daily-seed/schema.json
@@ -24,8 +24,11 @@
           "nature": {
             "$ref": "#/$defs/nature"
           },
-          "abilityIndex": {
-            "$ref": "#/$defs/abilityIndex"
+          "ability": {
+            "$ref": "#/$defs/ability"
+          },
+          "passive": {
+            "$ref": "#/$defs/passive"
           }
         },
         "required": ["speciesId"],
@@ -58,6 +61,13 @@
         },
         "passive": {
           "$ref": "#/$defs/passive"
+        },
+        "segments": {
+          "type": "integer",
+          "minimum": 1
+        },
+        "catchable": {
+          "type": "boolean"
         }
       },
       "required": ["speciesId"],
@@ -82,6 +92,24 @@
         "$ref": "#/$defs/forcedWave"
       }
     },
+    "trainerManipulations": {
+      "type": "array",
+      "items": {
+        "$ref": "#/$defs/trainerManipulation"
+      }
+    },
+    "challenges": {
+      "type": "array",
+      "items": {
+        "$ref": "#/$defs/challenge"
+      }
+    },
+    "mysteryEncounters": {
+      "type": "array",
+      "items": {
+        "$ref": "#/$defs/mysteryEncounter"
+      }
+    },
     "seed": {
       "type": "string"
     },
@@ -114,11 +142,6 @@
       "type": "integer",
       "exclusiveMinimum": 0
     },
-    "abilityIndex": {
-      "type": "integer",
-      "minimum": 0,
-      "maximum": 2
-    },
     "moveset": {
       "type": "array",
       "items": {
@@ -163,6 +186,52 @@
         }
       ],
       "additionalProperties": false
+    },
+    "trainerManipulation": {
+      "type": "object",
+      "properties": {
+        "waveIndex": {
+          "type": "integer",
+          "minimum": 1,
+          "maximum": 49
+        },
+        "isTrainer": {
+          "type": "boolean"
+        }
+      },
+      "required": ["waveIndex", "isTrainer"],
+      "additionalProperties": false
+    },
+    "challenge": {
+      "type": "object",
+      "properties": {
+        "id": {
+          "type": "integer",
+          "minimum": 0
+        },
+        "value": {
+          "type": "integer",
+          "minimum": 0
+        }
+      },
+      "required": ["id", "value"],
+      "additionalProperties": false
+    },
+    "mysteryEncounter": {
+      "type": "object",
+      "properties": {
+        "waveIndex": {
+          "type": "integer",
+          "minimum": 1,
+          "maximum": 49
+        },
+        "type": {
+          "type": "integer",
+          "minimum": 0
+        }
+      },
+      "required": ["waveIndex", "type"],
+      "additionalProperties": false
     }
   },
   "required": ["seed"],
diff --git a/src/data/pokemon-species.ts b/src/data/pokemon-species.ts
index 89ce0393912a..1343f7e4eb6d 100644
--- a/src/data/pokemon-species.ts
+++ b/src/data/pokemon-species.ts
@@ -1,6 +1,7 @@
 import { determineEnemySpecies } from "#app/ai/ai-species-gen";
 import type { AnySound } from "#app/battle-scene";
 import type { GameMode } from "#app/game-mode";
+import { timedEventManager } from "#app/global-event-manager";
 import { globalScene } from "#app/global-scene";
 import { speciesEggMoves } from "#balance/egg-moves";
 import { starterPassiveAbilities } from "#balance/passives";
@@ -31,7 +32,7 @@ import type { LevelMoves } from "#types/pokemon-level-moves";
 import type { StarterMoveset } from "#types/save-data";
 import type { EvolutionLevel, EvolutionLevelWithThreshold } from "#types/species-gen-types";
 import { randSeedFloat, randSeedGauss } from "#utils/common";
-import { getPokemonSpecies } from "#utils/pokemon-utils";
+import { getPokemonSpecies, getPokemonSpeciesForm } from "#utils/pokemon-utils";
 import { toCamelCase, toPascalCase } from "#utils/strings";
 import { argbFromRgba, QuantizerCelebi, rgbaFromArgb } from "@material/material-color-utilities";
 import i18next from "i18next";
@@ -338,7 +339,17 @@ export abstract class PokemonSpeciesForm {
       && female
       && ![SpeciesFormKey.MEGA, SpeciesFormKey.GIGANTAMAX].includes(formSpriteKey as SpeciesFormKey);
 
-    return `${showGenderDiffs ? "female__" : ""}${this.speciesId}${formSpriteKey ? `-${formSpriteKey}` : ""}`;
+    let spriteKey = `${showGenderDiffs ? "female__" : ""}${this.speciesId}${formSpriteKey ? `-${formSpriteKey}` : ""}`;
+
+    const replacement = timedEventManager.getEventSpriteReplacement(this.speciesId, formIndex);
+    if (replacement) {
+      const replacementFormSpriteKey = getPokemonSpecies(replacement.speciesId).forms[
+        replacement.formIndex
+      ]?.getFormSpriteKey(replacement.formIndex);
+      spriteKey = `${replacement.speciesId}${replacementFormSpriteKey ? `-${replacementFormSpriteKey}` : ""}`;
+    }
+
+    return spriteKey;
   }
 
   /** Compute the sprite ID of the pokemon form. */
@@ -363,7 +374,7 @@ export abstract class PokemonSpeciesForm {
    * @param formIndex optional form index for pokemon with different forms
    * @returns species id if no additional forms, index with formkey if a pokemon with a form
    */
-  getVariantDataIndex(formIndex?: number) {
+  getVariantDataIndex(formIndex?: number): string | number {
     let formkey: string | null = null;
     let variantDataIndex: number | string = this.speciesId;
     const species = getPokemonSpecies(this.speciesId);
@@ -373,6 +384,17 @@ export abstract class PokemonSpeciesForm {
         variantDataIndex = `${this.speciesId}-${formkey}`;
       }
     }
+
+    const replacement = timedEventManager.getEventSpriteReplacement(this.speciesId, formIndex);
+    if (replacement) {
+      formkey = species.forms[replacement.formIndex]?.getFormSpriteKey(replacement.formIndex);
+      if (formkey) {
+        variantDataIndex = `${replacement.speciesId}-${formkey}`;
+      } else {
+        variantDataIndex = replacement.speciesId;
+      }
+    }
+
     return variantDataIndex;
   }
 
@@ -380,7 +402,12 @@ export abstract class PokemonSpeciesForm {
     const variantDataIndex = this.getVariantDataIndex(formIndex);
     const isVariant =
       shiny && variantData[variantDataIndex] && variant !== undefined && variantData[variantDataIndex][variant];
-    return `pokemon_icons_${this.generation}${isVariant ? "v" : ""}`;
+
+    const replacementSpecies = timedEventManager.getEventSpriteReplacement(this.speciesId, formIndex);
+    const generation = replacementSpecies
+      ? getPokemonSpeciesForm(replacementSpecies.speciesId, replacementSpecies.formIndex).generation
+      : this.generation;
+    return `pokemon_icons_${generation}${isVariant ? "v" : ""}`;
   }
 
   getIconId(female: boolean, formIndex?: number, shiny?: boolean, variant?: number): string {
@@ -389,9 +416,14 @@ export abstract class PokemonSpeciesForm {
     }
 
     const variantDataIndex = this.getVariantDataIndex(formIndex);
+    const replacement = timedEventManager.getEventSpriteReplacement(this.speciesId, formIndex);
 
     let ret = this.speciesId.toString();
 
+    if (replacement) {
+      ret = replacement.speciesId.toString();
+    }
+
     const isVariant =
       shiny && variantData[variantDataIndex] && variant !== undefined && variantData[variantDataIndex][variant];
 
@@ -417,6 +449,11 @@ export abstract class PokemonSpeciesForm {
     }
 
     let formSpriteKey = this.getFormSpriteKey(formIndex);
+    if (replacement) {
+      formSpriteKey = getPokemonSpeciesForm(replacement.speciesId, replacement.formIndex).getFormSpriteKey(
+        replacement.formIndex,
+      );
+    }
     if (formSpriteKey) {
       switch (this.speciesId) {
         case SpeciesId.DUDUNSPARCE:
@@ -442,6 +479,13 @@ export abstract class PokemonSpeciesForm {
 
   getCryKey(formIndex?: number): string {
     let speciesId = this.speciesId;
+
+    const override = timedEventManager.getEventSpriteReplacement(this.speciesId, formIndex);
+    if (override) {
+      speciesId = override.speciesId;
+      formIndex = override.formIndex;
+    }
+
     if (this.speciesId > 2000) {
       switch (this.speciesId) {
         case SpeciesId.GALAR_SLOWPOKE:
diff --git a/src/field/pokemon.ts b/src/field/pokemon.ts
index e76401442a9b..4b876c8ddb97 100644
--- a/src/field/pokemon.ts
+++ b/src/field/pokemon.ts
@@ -2228,6 +2228,14 @@ export abstract class Pokemon extends Phaser.GameObjects.Container {
       return false;
     }
 
+    if (
+      globalScene.gameMode.isDaily
+      && this.customPokemonData.passive != null
+      && this.customPokemonData.passive !== -1
+    ) {
+      return true;
+    }
+
     const hasPassive = new BooleanHolder(this.passive);
     applyChallenges(ChallengeType.PASSIVE_ACCESS, this, hasPassive);
 
@@ -6507,8 +6515,11 @@ export class EnemyPokemon extends Pokemon {
 
       this.luck = (this.shiny ? this.variant + 1 : 0) + (this.fusionShiny ? this.fusionVariant + 1 : 0);
 
-      this.applyCustomDailyConfig();
-      this.applyCustomDailyBossConfig();
+      if (isDailyFinalBoss()) {
+        this.applyCustomDailyBossConfig();
+      } else {
+        this.applyCustomDailyConfig();
+      }
 
       if (this.hasTrainer() && globalScene.currentBattle) {
         const { waveIndex } = globalScene.currentBattle;
diff --git a/src/game-mode.ts b/src/game-mode.ts
index 1eca6c30ecf8..cb2e2befeecf 100644
--- a/src/game-mode.ts
+++ b/src/game-mode.ts
@@ -8,6 +8,7 @@ import {
   getDailyForcedWaveSpecies,
   getDailyStartingBiome,
   getDailyStartingMoney,
+  getDailyTrainerManipulation,
 } from "#data/daily-seed/daily-run";
 import { parseDailySeed } from "#data/daily-seed/daily-seed-utils";
 import { allSpecies } from "#data/data-lists";
@@ -208,6 +209,10 @@ export class GameMode implements GameModeConfig {
 
     // Daily spawns trainers on floors 5, 15, 20, 25, 30, 35, 40, and 45
     if (this.isDaily) {
+      const trainerManipulation = getDailyTrainerManipulation(waveIndex);
+      if (trainerManipulation != null) {
+        return trainerManipulation;
+      }
       return waveIndex % 10 === 5 || (!(waveIndex % 10) && waveIndex > 10 && !this.isWaveFinal(waveIndex));
     }
     if (waveIndex % 30 === (offsetGym ? 0 : 20) && !this.isWaveFinal(waveIndex)) {
diff --git a/src/overrides.ts b/src/overrides.ts
index 1448058bb7cb..0aff0ac8a4a0 100644
--- a/src/overrides.ts
+++ b/src/overrides.ts
@@ -6,6 +6,8 @@ import { AbilityId } from "#enums/ability-id";
 import { BattleType } from "#enums/battle-type";
 import { BerryType } from "#enums/berry-type";
 import { BiomeId } from "#enums/biome-id";
+import { BiomePoolTier } from "#enums/biome-pool-tier";
+import { Challenges } from "#enums/challenges";
 import { EggTier } from "#enums/egg-type";
 import { FormChangeItem } from "#enums/form-change-item";
 import { MoveId } from "#enums/move-id";
@@ -31,7 +33,7 @@ import type { IntClosedRange, TupleOf } from "type-fest";
 /**
  * This comment block exists to prevent IDEs from automatically removing unused imports
  * {@linkcode BerryType}, {@linkcode EvolutionItem}, {@linkcode FormChangeItem}
- * {@linkcode Stat}, {@linkcode PokemonType}
+ * {@linkcode Stat}, {@linkcode PokemonType} {@linkcode Challenges} {@linkcode BiomePoolTier}
  */
 
 /**
diff --git a/src/phases/command-phase.ts b/src/phases/command-phase.ts
index b8b25871d22a..ad659013f508 100644
--- a/src/phases/command-phase.ts
+++ b/src/phases/command-phase.ts
@@ -3,6 +3,8 @@ import { globalScene } from "#app/global-scene";
 import { getPokemonNameWithAffix } from "#app/messages";
 import { speciesStarterCosts } from "#balance/starters";
 import { TrappedTag } from "#data/battler-tags";
+import { getDailyEventSeedBoss } from "#data/daily-seed/daily-run";
+import { isDailyFinalBoss } from "#data/daily-seed/daily-seed-utils";
 import { AbilityId } from "#enums/ability-id";
 import { ArenaTagSide } from "#enums/arena-tag-side";
 import { ArenaTagType } from "#enums/arena-tag-type";
@@ -368,6 +370,7 @@ export class CommandPhase extends FieldPhase {
       .some(p => p.isActive() && !dexData[p.species.speciesId].caughtAttr);
     const missingMultipleStarters =
       gameData.getStarterCount(d => !!d.caughtAttr) < Object.keys(speciesStarterCosts).length - 1;
+    const isCatchableDailyBoss = isDailyFinalBoss() && (getDailyEventSeedBoss()?.catchable ?? false);
 
     if (biomeId === BiomeId.END && battleType === BattleType.WILD) {
       if (
@@ -381,7 +384,7 @@ export class CommandPhase extends FieldPhase {
         (isClassic && isClassicFinalBoss && missingMultipleStarters)
         || (isFullFreshStart && isClassicFinalBoss)
         || (isEndless && isEndlessMinorBoss)
-        || isDaily
+        || (isDaily && !isCatchableDailyBoss)
       ) {
         // Uncatchable final boss in classic, endless and daily
         this.queueShowText("battle:noPokeballForceFinalBoss");
@@ -422,6 +425,7 @@ export class CommandPhase extends FieldPhase {
 
     const isChallengeActive = globalScene.gameMode.hasAnyChallenges();
     const isFinalBoss = globalScene.gameMode.isBattleClassicFinalBoss(globalScene.currentBattle.waveIndex);
+    const isCatchableDailyBoss = isDailyFinalBoss() && (getDailyEventSeedBoss()?.catchable ?? false);
 
     const numBallTypes = 5;
     if (cursor < numBallTypes) {
@@ -441,7 +445,7 @@ export class CommandPhase extends FieldPhase {
           return false;
         }
         // When facing any other boss, Master Ball can always be used, and we use the standard message.
-        if (cursor < PokeballType.MASTER_BALL) {
+        if (isCatchableDailyBoss || cursor < PokeballType.MASTER_BALL) {
           this.queueShowText("battle:noPokeballStrong");
           return false;
         }
diff --git a/src/phases/title-phase.ts b/src/phases/title-phase.ts
index 3acddae611a0..7d6fcfe1d486 100644
--- a/src/phases/title-phase.ts
+++ b/src/phases/title-phase.ts
@@ -6,7 +6,7 @@ import { globalScene } from "#app/global-scene";
 import Overrides from "#app/overrides";
 import { Phase } from "#app/phase";
 import { bypassLogin } from "#constants/app-constants";
-import { getDailyRunStarters } from "#data/daily-seed/daily-run";
+import { getDailyRunStarters, startDailyEventChallenges } from "#data/daily-seed/daily-run";
 import { modifierTypes } from "#data/data-lists";
 import { Gender } from "#data/gender";
 import { BattleType } from "#enums/battle-type";
@@ -228,11 +228,12 @@ export class TitlePhase extends Phase {
 
       const generateDaily = (seed: string) => {
         globalScene.gameMode = getGameMode(GameModes.DAILY);
-        // Daily runs don't support all challenges yet (starter select restrictions aren't considered)
-        timedEventManager.startEventChallenges();
 
         seed = globalScene.gameMode.trySetCustomDailyConfig(seed);
 
+        // Daily runs don't support all challenges yet (starter select restrictions aren't considered)
+        startDailyEventChallenges();
+
         globalScene.setSeed(seed);
         globalScene.resetSeed();
 
@@ -244,7 +245,7 @@ export class TitlePhase extends Phase {
         // TODO: Dedupe this
         const party = globalScene.getPlayerParty();
         const loadPokemonAssets: Promise<void>[] = [];
-        for (const starter of starters) {
+        for (const [index, starter] of starters.entries()) {
           const species = getPokemonSpecies(starter.speciesId);
           const starterFormIndex = starter.formIndex;
           const starterGender =
@@ -266,6 +267,14 @@ export class TitlePhase extends Phase {
             starterPokemon.tryPopulateMoveset(starter.moveset, true);
           }
 
+          const customStarterConfig = globalScene.gameMode.dailyConfig?.starters?.[index];
+          if (customStarterConfig?.ability != null) {
+            starterPokemon.customPokemonData.ability = customStarterConfig.ability;
+          }
+          if (customStarterConfig?.passive != null) {
+            starterPokemon.customPokemonData.passive = customStarterConfig.passive;
+          }
+
           party.push(starterPokemon);
           loadPokemonAssets.push(starterPokemon.loadAssets());
         }
diff --git a/src/plugins/i18n.ts b/src/plugins/i18n.ts
index 971b5ee306a9..4cc6cd5e86a6 100644
--- a/src/plugins/i18n.ts
+++ b/src/plugins/i18n.ts
@@ -1,3 +1,4 @@
+import { timedEventManager } from "#app/global-event-manager";
 import { getCachedUrl } from "#utils/fetch-utils";
 import { toKebabCase } from "#utils/strings";
 import i18next from "i18next";
@@ -227,3 +228,18 @@ await i18next
   );
 
 //#endregion
+
+//#region Event Proxy
+
+if (timedEventManager.hasEventTextReplacement()) {
+  console.warn("Event text replacements are active.");
+  i18next.t = new Proxy(i18next.t.bind(i18next), {
+    apply(target, _, args: [key: string, options?: any]) {
+      const key = timedEventManager.getEventTextReplacement(args[0]);
+      args[0] = key;
+      return target(...args);
+    },
+  });
+}
+
+//#endregion
diff --git a/src/timed-event-manager.ts b/src/timed-event-manager.ts
index ca041a8694c3..5e1a79aca449 100644
--- a/src/timed-event-manager.ts
+++ b/src/timed-event-manager.ts
@@ -1,14 +1,17 @@
-import { globalScene } from "#app/global-scene";
 import { SHINY_CATCH_RATE_MULTIPLIER } from "#balance/rates";
 import { CLASSIC_CANDY_FRIENDSHIP_MULTIPLIER } from "#balance/starters";
+import { allSpecies } from "#data/data-lists";
 import type { PokemonSpeciesFilter } from "#data/pokemon-species";
 import type { MysteryEncounterTier } from "#enums/mystery-encounter-tier";
 import type { MysteryEncounterType } from "#enums/mystery-encounter-type";
 import type { SpeciesId } from "#enums/species-id";
 import type { ModifierTypeKeys } from "#modifiers/modifier-type";
 import type { EventEncounter, EventMysteryEncounterTier, EventWeatherPools, TimedEvent } from "#types/events";
+import { randSeedShuffle } from "#utils/common";
 import { getPokemonSpecies } from "#utils/pokemon-utils";
+import i18next from "i18next";
 import { timedEvents } from "./data/balance/timed-events";
+import { globalScene } from "./global-scene";
 
 export class TimedEventManager {
   /**
@@ -16,6 +19,7 @@ export class TimedEventManager {
    * Used to disable events in testing.
    */
   private disabled: boolean;
+  private cachedReplacementMap: Map<number, { speciesId: SpeciesId; formIndex: number }> | null = null;
 
   isActive(event: TimedEvent) {
     if (this.disabled) {
@@ -204,13 +208,99 @@ export class TimedEventManager {
     return bgm;
   }
 
+  public getEventSpriteReplacement(
+    species: SpeciesId,
+    formIndex = 0,
+  ): {
+    speciesId: SpeciesId;
+    formIndex: number;
+  } | null {
+    const event = this.activeEvent();
+    if (!event) {
+      return null;
+    }
+    const sprites = event?.sprites;
+    if (!sprites) {
+      return null;
+    }
+    const eventSpriteReplacements = sprites.replacements;
+    const fillRandom = sprites.fillRandom ?? false;
+
+    for (const esr of eventSpriteReplacements) {
+      const [sourceSpeciesIdStr, sourceFormIndexStr] = esr[0].split("/");
+      if (sourceSpeciesIdStr === species.toString() && (sourceFormIndexStr ?? "0") === formIndex.toString()) {
+        const [targetSpeciesIdStr, targetFormIndexStr] = esr[1].split("/");
+        return { speciesId: Number(targetSpeciesIdStr) as SpeciesId, formIndex: Number(targetFormIndexStr ?? "0") };
+      }
+    }
+
+    if (fillRandom) {
+      // Multiply by 100000 to avoid collisions
+      const key = species * 100_000 + formIndex;
+      if (!this.cachedReplacementMap) {
+        this.fillRandomSpriteReplacements();
+      }
+      return this.cachedReplacementMap!.get(key) ?? null;
+    }
+    return null;
+  }
+
   /**
-   * Activate any challenges on {@linkcode globalScene.gameMode} for the currently active event
+   * Assign each species/form pair a random other species/form pair for sprite replacement.
    */
-  startEventChallenges(): void {
-    for (const eventChal of this.activeEvent()?.dailyRunChallenges ?? []) {
-      globalScene.gameMode.setChallengeValue(eventChal.challenge, eventChal.value);
+  private fillRandomSpriteReplacements() {
+    if (!this.cachedReplacementMap) {
+      this.cachedReplacementMap = new Map();
+      const allPairs: { speciesId: SpeciesId; formIndex: number }[] = [];
+      for (const species of allSpecies) {
+        const formCount = species.forms.length || 1;
+        for (let f = 0; f < formCount; f++) {
+          allPairs.push({ speciesId: species.speciesId, formIndex: f });
+        }
+      }
+      globalScene.executeWithSeedOffset(
+        () => {
+          const shuffled = randSeedShuffle([...allPairs]);
+          for (let i = 0; i < allPairs.length; i++) {
+            const sourceKey = allPairs[i].speciesId * 100_000 + allPairs[i].formIndex;
+            this.cachedReplacementMap!.set(sourceKey, shuffled[i]);
+          }
+        },
+        0,
+        this.activeEvent()!.name,
+      );
+    }
+  }
+
+  /**
+   * Return the key replacement for the given i18n key if it exists in the active event, otherwise return the original key.
+   * @param key The i18n key to check for a replacement
+   * @returns The replacement key if it exists, otherwise the original key
+   */
+  public getEventTextReplacement(key: string): string {
+    const event = this.activeEvent();
+    if (!event || !event.textReplacements) {
+      return key;
+    }
+    for (const [source, target] of event.textReplacements) {
+      if (key === source && i18next.exists(target)) {
+        return target;
+      }
+    }
+    return key;
+  }
+
+  /**
+   * Check if the current active event has any text replacements. \
+   * This is used to determine wheater the i18next proxy should be loaded.
+   * @returns Whether the active event has text replacements
+   */
+  public hasEventTextReplacement(): boolean {
+    const event = this.activeEvent();
+    if (!event) {
+      return false;
     }
+    return event.textReplacements != null && event.textReplacements.length > 0;
   }
 
   getEventDailyStartingItems(): readonly ModifierTypeKeys[] {