I was gonna do something like this. But I sorely doubt anyone will pick a partner who they think might screw them later. Yet I like the idea of teamwork!
So let's also make partners M:tG cards. When a partner is selected, they must create an Avatar of themselves. The avatar is constructed as follows.
-Name: The partner selects a name for the avatar.
-Colour(s): The partner selects a colour for his avatar. The colour may be red, blue, green, black, white, a combination of the above (red blue, for example).
-Type: The partner selects a type for his avatar, e.g. goblin, troll, wizard, robot.
-Power/Toughness: The partner may divide eight points between power and toughness. Whole numbers only, and toughness must be at least *one* point.
-Abilities: The partner may select one of the following abilities. (First Strike, Haste, Flying, Trample, Regenerate: Ten Points, Regenerate: One Vote, Vigilance, Shadow, Protection From (one colour), Defender)
If a partner is killed, the player should lose the vote the partner provides until a replacement can be found (with some kind of delay.)
The details on how a partner is chosen probably need to change, as well as exactly how the vote is handled. Also some method for actually throwing down and having a fight would be highly desired.