RainMate

This is a variation of chess with the addition of a 'rain piece'

At the beginning of the game, white chooses one of their pieces (except the king) to be a rain piece. The rain piece is highlighted blue.

The rain piece can't be killed by a king.

If the rain piece is killed, the killing piece becomes the same type (for example, if a knight kills a rain queen, the knight becomes a queen).

If there's enough interest in this game, I might add some animations.