Korvold, the Cursed King

Flying, trample
When Korvold deal damage to a player, that
player may sacrifice a creature, if they do, you
gain 3 life, if they don't, they loose 3 life
{2}, {t}, sacrifice a creature: put a +1/+1 counter
on Korvold
{b/g}{b/r}{r/g}, {t}: create a 0/1 white Slave
creature token