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Enthralling Victor

When Enthralling Victor enters, gain control of target creature an opponent controls with power 2 or less until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

The List

Battlebond

When Enthralling Victor enters the battlefield, gain control of target creature an opponent controls with power 2 or less until end of turn. Untap that creature. It gains haste until end of turn.

Masters 25

Magic Origins

When Enthralling Victor enters the battlefield, gain control of target creature an opponent controls with power 2 or less until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

Enthralling Victor's ability can target a creature that's already untapped. You'll still gain control of it and it will gain haste.

Once Enthralling Victor's ability resolves and you gain control of a creature, raising its power above 2 won't cause you to lose control of it. Similarly, it doesn't matter if Enthralling Victor leaves the battlefield or you lose control of Enthralling Victor. You'll keep control of the creature that was the target of the ability until the end of the turn.