Caroling

Interrupt target player's action, that action is
stopped and reversed, that player may choose to
pay X, where X is the number of creatures you control with power 2 or less. If they don't,
creatures they control get -X/-X until end of
their turn.
{1} Target player must sing a full Christmas song
of your choice, or allow you to deal X damage to
one of their creatures, you may use this ability on yourself and receive 2 life.