All creatures get -2/-2 until end of turn. If a creature an opponent controls would die this turn, exile it instead.
Aclazotz laughed as the dark shards closed around Chimil, plunging the Core into unnatural darkness. At long last, his bloody reign would begin.
(10/11/2023)
While the -2/-2 applies only to creatures that are on the battlefield as Malicious Eclipse resolves, the replacement effect applies to all creatures opponents control that turn, including ones that enter the battlefield after Malicious Eclipse resolves, noncreatures that become creatures after Malicious Eclipse resolves, and creatures that become controlled by opponents after Malicious Eclipse resolves.
(10/11/2023)
Creatures opponents control will be exiled if they would die for any reason that turn, not just if they die by being reduced to 0 or less toughness by Malicious Eclipse.
