Siren's Call [Alpha Edition] Gladiator one must assassinate the previous

one must assassinate the previous king

Fling deals damage equal to the sacrificed creature's power to any target

Set: Magic 2013 Type: Creature — Hydra Rarity: Mythic Cost: {X}{G}{G} Primordial Hydra enters the battlefield with X +1/+1 counters on it

Set: Worldwake Type: Legendary Land Rarity: Mythic Colorless Eldrazi spells you cast cost {2} less to cast

Siren's Call [Alpha Edition] Gladiator one must assassinate the previousSet: Alpha Edition Type: Instant Rarity: Uncommon Cost: {U} Cast this spell only during an opponent's turn, before attackers are declared. Creatures the active player controls attack this turn if able. At the beginning of the next end step, destroy all non Wall creatures that player controls that didn't attack this turn. Ignore this effect for each creature the player didn't control continuously since the beginning of the turn.