What Have I Done?

This.

When someone feels a deep guilt after viewing the aftermath of their actions. Such actions could have been murdering many people, pranking somebody, destroying a city or town, or arguing with them and saying something that makes them run away in tears. If an antagonist plays this UnTrash, it's often because they just had a Change Of Heart after seeing what they've done to other people and, if this UnTrash is powerful enough, will lead to them vowing to end their evil ways and join the forces of good.