Now, I said I had another idea. A six team game; Each with their own goals (usually elimination of two others). Every player belongs to TWO teams.
As well, each player has TWO power roles (often a variation on the seer, hence why Grimmace's second idea is similar). There is no power role which only one player can have (Each will be assigned to four or more, or not at all).
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Team A would want to eliminate teams B and F.
Team B would want to eliminate teams A and C.
Team C would want to eliminate teams B and D.
Team D would want to eliminate Teams C and E.
Team E would want to eliminate teams D and F.
Team F would want to eliminate teams E and A.
For each team, there are three teams that a member could still be a part of.
Someone from Team A could also be a part of Teams C, D, or E.
Someone from Team B could also be a part of Teams D, E, or F.
Someone from Team C could also be a part of Teams E, F, or A.
Someone from Team D could also be a part of Teams F, A, or B.
Someone from Team E could also be a part of Teams A, B, or C.
Someone from Team F could also be a part of Teams B, C, or D.
A minimum of Three teams must be eliminated for the game to end. Up to three teams can achieve victory simultaneously.
Obviously once I decide on a theme, these teams/factions will have actual names. Everyone in a faction knows who all else is in that faction, but does not know what their powers/other factions are (unless their both in the same two factions). They're allowed to talk, and work together, but they may also be working against each other without knowing it! Would be a good idea not to talk about which factions you also belong to, and not mention your roles, maybe.
As to roles... Well, nothing should be team specific. Maybe certain roles "cannot show up in a certain faction", but no role can "only show up in a certain faction". Someone can use both their powers each night, unless it has a cool down.