Sylvia Brightspear

The triggered ability of the “partner with” keyword still triggers in a Commander game. If your other commander has somehow ended up in your library, you can find it. You can also target another player who might have that card in their library.

“Partner with [name]” represents two abilities. The first is a triggered ability: “When 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.”

Once the game begins, your two commanders are tracked separately. If you cast one, you won’t have to pay an additional {2} the first time you cast the other. A player loses the game after having been dealt 21 damage from one of them, not from both of them combined. Command Beacon’s effect puts one into your hand from the command zone, not both.

If your Commander deck has two commanders, you can only include cards whose own color identities are also found in your commanders’ combined color identities. If Khorvath and Sylvia are your commanders, your deck may contain cards with red and/or white in their color identity, but not blue, black, or green.

To have two commanders, both must have the partner ability (featured in the Magic: The Gathering—Commander™ (2016 Edition) set) or corresponding “partner with” abilities as the game begins. A creature with a “partner with” ability can’t partner with any creature other than its designated partner. Losing a partner ability during the game doesn’t cause either to cease to be your commander.

An effect that checks whether you control your commander is satisfied if you control one or both of your two commanders.