You have a not-small group of players. The game has a series of faceoffs, and the last two players standing win.
For a faceoff, one player known as the "attacker" is chosen randomly from among the surviving players. Then one player known as the "defender" is chosen randomly from among the surviving players. The attacker may choose one "out" player, who can not participate in the faceoff. One player can volunteer to be part of the attacking team, and one player can volunteer to be part of the defendng team. One of these "secondary" players is not officially part of the faceoff until he has touched the die.
So there are two to four players divided into two sides, attackers and defenders, with red dice and white dice respectively. All players involved in the faceoff roll at once, more or less. The team that has the die with the highest number is safe. The player with the lowest number on the losing team is out of the game. If both teams get the highest number, it's a tie and nobody loses. If the losing side has two players with the same number, both players are out of the game.
Q: Why would someone volunteer to participate in a faceoff?
A: If Ralph decides to stand by Sally on the attacking team against a single defender, the odds of the attacking team winning improve. Ralph gets nothing from this; in fact it is dangerous for Ralph. However, if Sally also does the same thing for Ralph, then Ralph and Sally do better than if they both played alone.
Do you know who Jane's ally is? Note that people can be fair weather friends.
Let people mingle and eat Cheetos before the game starts.
This game could probably use an administrator to keep things on track.
You could draw cards to quickly determine attacker and defender, or use
more thematic and smaller dice.
On average one player will lose the game per faceoff. If you have twelve players and ten turns with multiple dice rolls and nervous negotiations, you can imagine how long a game would be.
I tried 100 rolls with A and B attackers and C defender, and got the following results:
A died 6
B died 9
A and B died 5 (I calculate should be 7%)
C died 63