Invasion of Ixalan // Belligerent Regisaur
Battle — Siege // Creature — Dinosaur
Rulings (16)
If a Siege never had defense counters on it (perhaps because a permanent became a copy of one), it can’t have its last defense counter removed. It will be put into its owner’s graveyard. You won’t exile it or cast the other face.
If a permanent that is represented by a transforming double-faced card becomes a copy of a Siege, it will be exiled as that Siege’s triggered ability resolves, then it will be cast transformed. Note that this applies only to transforming double-faced cards, not to modal double-faced cards that can normally be played using either face.
If a non-battle permanent that is already on the battlefield become a copy of a Siege, its controller chooses one of their opponents to be that battle’s protector. However, it will most likely be put into its owner’s graveyard because it has no defense counters (see below).
Legality
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