Omnon, Endbringer

Flying, vigilance, annihilator 1
Whenever a player sacrifices a permanent,
creatures you control get +1/+1 until end of turn.
{x}{u}{b}{r}: Create X 1/1 blue, black and red
Shadow creature tokens with flying and haste.
{u}{u}{b}{b}{r}{r}: Creatures you control gain
double strike until end of turn.