Raes Horgast, the Instigator

Generic mana costs of creatures may be payed
with life instead of mana.
Whenever a player pays life, target creature they control gains haste and is goaded. If that creature
is controlled by an opponent it also gains "exile
this creature at the beginning of the next end
step." (Until your next turn, that creature attacks
each combat if able and attacks a player other than
you if able.)