wotc
Use the greatest power among Mutants you control as Vault 87's last ability resolves to determine how many cards to draw.
Use the greatest power among Mutants you control as Vault 87's last ability resolves to determine how many cards to draw.
The target of Vault 87's first chapter ability only needs to be a non-Mutant when that ability is put onto the stack and when that ability resolves. The control effect won't end if it later becomes a Mutant (perhaps because of the effect of the second chapter ability).
If Vault 87 leaves the battlefield before its first chapter ability resolves, you won't gain control of the target creature at all.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Nicholas Gregory
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