Sidar Kondo of Jamuraa

To have two commanders, both must have the partner ability as the game begins. Losing the ability during the game doesn't cause either to cease to be your commander.

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 any one of them, not from both of them combined.

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 Falthis and Kediss are your commanders, your deck may contain cards with black and/or red in their color identity, but not cards with green, white, or blue.

Sidar Kondo's blocking restriction applies to creatures your opponents control even when an opponent is being attacked by a player other than you.

Both commanders start in the command zone, and the remaining 98 cards (or 58 cards in a Commander Draft game) of your deck are shuffled to become your library.

Once an attacking creature has been blocked by a creature without flying or reach, reducing its power to 2 or less won't change or undo that block.