diff --git a/AquaMai.Mods/GameSystem/UnstableRate.cs b/AquaMai.Mods/GameSystem/UnstableRate.cs
new file mode 100644
index 00000000..d8b0c0e9
--- /dev/null
+++ b/AquaMai.Mods/GameSystem/UnstableRate.cs
@@ -0,0 +1,207 @@
+using AquaMai.Config.Attributes;
+using HarmonyLib;
+using MAI2.Util;
+using Manager;
+using Monitor;
+using Process;
+using UnityEngine;
+
+namespace AquaMai.Mods.GameSystem;
+
+[ConfigSection(
+    name: "UnstableRate",
+    en: "Show information about the exact timing for each hit during gameplay in the center of the screen.")]
+public class UnstableRate
+{
+    // The playfield goes from bottom left (-1080, -960) to top right (0, 120)
+    private const float BaselineHeight = -480;
+    private const float BaselineCenter = -540;
+    private const float BaselineHScale = 25;
+    private const float CenterMarkerHeight = 20;
+
+    private const float JudgeHeight = 20;
+    private const float JudgeFadeDelay = 1;
+    private const float JudgeFadeTime = 1;
+    private const float JudgeAlpha = 0.8f;
+
+    private const float LineThickness = 4;
+
+    private const float TimingBin = 16.666666f;
+
+    private struct Timing
+    {
+        // Timings are in multiple of TimingBin (16.666666ms)
+        public int windowStart;
+        public int windowEnd;
+        public Color color;
+    }
+
+    private static readonly Timing[] Timings =
+    [
+        new() { windowStart = 0, windowEnd = 1, color = new Color(0.133f, 0.712f, 0.851f) }, // Critical
+        new() { windowStart = 1, windowEnd = 3, color = new Color(0.122f, 0.484f, 0.861f) }, // Perfect
+        new() { windowStart = 3, windowEnd = 6, color = new Color(0.102f, 0.731f, 0.078f) },  // Great
+        new() { windowStart = 6, windowEnd = 9, color = new Color(0.925f, 0.730f, 0.110f) },  // Good
+    ];
+    private static readonly Timing Miss = new() {windowStart = 999, windowEnd = 999, color = Color.grey };
+    private static readonly Material LineMaterial = new(Shader.Find("Sprites/Default"));
+
+    private static GameMonitor _monitor;
+
+    [HarmonyPostfix]
+    [HarmonyPatch(typeof(GameProcess), "OnStart")]
+    public static void OnGameProcessStart(GameProcess __instance)
+    {
+        _monitor = Traverse.Create(__instance).Field("_monitors").GetValue<GameMonitor[]>()[0];
+
+        // Set up the baseline (the static part of the display)
+        SetupBaseline();
+    }
+
+    [HarmonyPostfix]
+    [HarmonyPatch(typeof(NoteBase), "Judge")]
+    public static void OnJudge(NoteBase __instance)
+    {
+        // How many milliseconds early or late the player hit
+        var msec = Traverse.Create(__instance).Field("JudgeTimingDiffMsec").GetValue<float>();
+
+        // Account for the offset
+        var optionJudgeTiming = Singleton<GamePlayManager>.Instance.GetGameScore(0).UserOption.GetJudgeTimingFrame();
+        msec -= optionJudgeTiming * TimingBin;
+
+        // Don't process misses
+        var timing = GetTiming(msec);
+        if (timing.windowStart == Miss.windowStart)
+        {
+            return;
+        }
+
+        // Create judgement tick
+        var line = CreateLine();
+
+        line.SetPosition(0, new Vector3(BaselineCenter + BaselineHScale * (msec / TimingBin), BaselineHeight + JudgeHeight, 0));
+        line.SetPosition(1, new Vector3(BaselineCenter + BaselineHScale * (msec / TimingBin), BaselineHeight - JudgeHeight, 0));
+
+        line.startColor = timing.color;
+        line.endColor = timing.color;
+
+        // Setup fade-out
+        var judgeTick = line.gameObject.AddComponent<JudgeTick>();
+        judgeTick.SetLine(line);
+
+        // Destroy it once the fade-out is over
+        Object.Destroy(line.gameObject, JudgeFadeDelay + JudgeFadeTime);
+    }
+
+    [HarmonyPostfix]
+    [HarmonyPatch(typeof(HoldNote), "JudgeHoldHead")]
+    public static void OnJudgeHold(HoldNote __instance)
+    {
+        // The calculations are the same for the hold note heads
+        OnJudge(__instance);
+    }
+
+    private static void SetupBaseline()
+    {
+        LineRenderer line;
+
+        // Draw lines from the center outwards in both directions
+        for (float sign = -1; sign <= 1; sign += 2)
+        {
+            // Draw each timing window in a different color
+            foreach (var timing in Timings)
+            {
+                line = CreateLine();
+
+                line.SetPosition(0, new Vector3(BaselineCenter + sign * BaselineHScale * timing.windowStart, BaselineHeight, 0));
+                line.SetPosition(1, new Vector3(BaselineCenter + sign * BaselineHScale * timing.windowEnd, BaselineHeight, 0));
+
+                line.startColor = timing.color;
+                line.endColor = timing.color;
+            }
+        }
+
+        // Center marker
+        line = CreateLine();
+
+        // Setting z-coordinate to -1 to make sure it stays in the foreground
+        line.SetPosition(0, new Vector3(BaselineCenter, BaselineHeight + CenterMarkerHeight, -1));
+        line.SetPosition(1, new Vector3(BaselineCenter, BaselineHeight - CenterMarkerHeight, -1));
+
+        line.startColor = Color.white;
+        line.endColor = Color.white;
+    }
+
+    private static LineRenderer CreateLine()
+    {
+        var obj = new GameObject();
+        obj.transform.SetParent(_monitor.transform);
+
+        // We can't add the line directly as a component of the monitor, because it can only
+        // have one LineRenderer component at a time.
+        var line = obj.AddComponent<LineRenderer>();
+        line.material = LineMaterial;
+        line.startWidth = LineThickness;
+        line.endWidth = LineThickness;
+        line.positionCount = 2;
+        line.numCapVertices = 6; // Make the ends round
+
+        return line;
+    }
+
+    private static Timing GetTiming(float msec)
+    {
+        // Convert from milliseconds to multiples of TimingBin, the same unit used in
+        // the lookup table.
+        var hitTime = Mathf.Abs(msec) / TimingBin;
+
+        // Search the timing interval that the hit lands in
+        foreach (var timing in Timings)
+        {
+            // Using >= and < just like NoteJudge
+            if (hitTime >= timing.windowStart && hitTime < timing.windowEnd)
+            {
+                return timing;
+            }
+        }
+
+        return Miss;
+    }
+
+    // Handles the fade-out of judgment ticks
+    private class JudgeTick : MonoBehaviour
+    {
+        private float _elapsedTime;
+        private LineRenderer _line;
+        private Color _initialColor;
+
+        public void SetLine(LineRenderer line)
+        {
+            _line = line;
+            _initialColor = line.startColor;
+
+            // We needed to store the full color above, so we didn't apply the alpha before
+            var color = _initialColor;
+            color.a *= JudgeAlpha;
+
+            _line.startColor = color;
+            _line.endColor = color;
+        }
+
+        public void Update()
+        {
+            _elapsedTime += Time.deltaTime;
+
+            // Only start the fade-out after a short delay
+            if (_elapsedTime < JudgeFadeDelay)
+                return;
+
+            Color color = _initialColor;
+
+            color.a = JudgeAlpha * (1.0f - Mathf.Clamp01((_elapsedTime - JudgeFadeDelay) / JudgeFadeTime));
+
+            _line.startColor = color;
+            _line.endColor = color;
+        }
+    }
+}