This is possible by setting two teams to be the same color, and then checking 'have same-color teams allied' or some button like that.
Slayer "Alliances"Set one team "allied" to a seperate team. For example, a 4-way TDM, but I want a certain team to be "allied" to another one. Any teams "allied" to another team(Ex. Blue Team allied with Magenta team) will either A)be unable to damage eachother or B)Die when they kill any of the allies from the other team.
What about "Die if you kill the same color team"?
I think there's a setting for auto-killing people when they kill someone w/friendly fire as well, although I don't know if it works for allied teams.