DestroyCardAction ResponsibleCard is not used like you'd think

[jamespicone]

DestroyCardAction has a ResponsibleCard property, which you set via the responsibleCard argument of SelectAndDestroyCards. You might expect that cards that care about who destroys cards (e.g., Savage Mana, La Capitan) would pay attention to that property, but they don't. In practice the ResponsibleCard property is only used to detect whether Aeon Men are destroyed by Oblivaeon and for promo unlocks, and cards that care about the source of a destroy effect look at the CardSource of the destroy effect.