If the affected creature gains an ability after Gift of Tusks resolves, it will keep that ability.
Gift of Tusks
Gift of Tusks doesn’t counter abilities that have already triggered or been activated. In particular, there is no way to cast this spell to stop a creature’s ability that says “At the beginning of your upkeep,” “When this creature enters the battlefield,” or similar from triggering.
The creature will lose all other colors and creature types, but it will retain any other card types (such as artifact) or supertypes (such as legendary) it may have.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Kev Walker
Card data via Scryfall. Rarix is fan-made; not endorsed by the rights holders.
