Creature â Human Warrior
Partner with Proud Mentor (When this creature enters the battlefield, target player may put Proud Mentor into their hand from their library, then shuffle.)
Whenever Impetuous Protege attacks, it gets +X/+0 until end of turn, where X is the greatest power among tapped creatures your opponents control.
The value of X is determined only as Impetuous Protegeâ€™s last ability resolves. Once that happens, the value of X wonâ€™t change later in the turn even if the greatest power among your opponentsâ€™ tapped creatures changes.
Note that the target player searches their library (which may be affected by effects such as that of Stranglehold) and that the card they find is revealed, even though these words arenâ€™t included in the abilityâ€™s reminder text.
If the greatest power among tapped creatures your opponents control is negative, X is considered to be 0. The same is true if your opponents control no tapped creatures.
A nonlegendary creature canâ€™t be your commander, even if it has a â€œpartner withâ€ ability.
â€œPartner with [name]â€ represents two abilities. The first is a triggered ability: â€œWhen this permanent enters the battlefield, target player may search their library for a card named [name], reveal it, put it into their hand, then shuffle their library.â€