Loki, The Mischievous

Deathtouch, Myth
Loki, The Mischievous isn't a creature as
long as a player's life total is 20 or below.
When Loki, The Mischievous enters the battlefield
each player sacrifices a creature.
{1}{b}•Target creature gets -2/-2 until end of turn.
{1}{g}•Target creature gets +2/+2 until end of turn.
{1}{u}•Each player discards a card
from the top of their library.