Siren's Call
Instant
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.
イラスト：
Limited Edition Beta#78アンコモン英語適正
裁定
It will require creatures with Haste to attack since they are able, but it won’t destroy them if they don’t for some reason.
The creature is destroyed if it does not attack because it simply can’t do so legally.
This will destroy creatures that weren’t able to attack because they had been previously tapped.
If a turn has multiple combat phases, this spell can only be cast before the beginning of the Declare Attackers Step of the first combat phase in that turn.