Whenever this creature or another creature dies, target player loses 1 life and you gain 1 life.

Mutate {4}{B}{B} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.) Flash Flying Whenever this creature mutates, destroy target creature or planeswalker an opponent controls.

Mutate {1}{G}{G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.) Reach, trample Whenever this creature mutates, destroy target artifact or enchantment an opponent controls.

Mutate {2}{W/B}{W/B} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.) Whenever this creature mutates, return target creature card with mana value 3 or less from your graveyard to the battlefield.

Polukranos enters with six +1/+1 counters on it. It escapes with twelve +1/+1 counters on it instead. If damage would be dealt to Polukranos while it has a +1/+1 counter on it, prevent that damage and remove that many +1/+1 counters from it. {1}{B}{G}: Polukranos fights another target creature. Escape—{4}{B}{G}, Exile six other cards from your graveyard.

Kicker {4}{B} When you cast this spell, if it was kicked, each player loses half their life, rounded up. Scourge of the Skyclaves's power and toughness are each equal to 20 minus the highest life total among players.