I wanted a version of the game "Werewolf" I could play with a large number of Cub Scouts (aged 7-10) so I decided to base it on Spy vs Spy...

Version 1:

Player Ratios:
Players:White:Grey:Black
10:2:1:7

Rules:
Same as Werewolf where...
White Spies is the same as Villagers
Black Spies is the same as Werewolves
Grey Spies is the same as the Seers
White Spies and Black Spies just "Capture" each other

Winning Conditions:
White and Grey Spies win by eliminating Black.
Black Spies win by having more of them than White and Grey.

Version 2:

Player Ratios:
Players:White:Grey:Black
20:4:3:13

Rules:
Same as the other except this time, Grey Spies acts as a double agents.
Grey Spies wakes with Black Spies at night, pretending to be Black, to help capture White Spies
During the day Grey Spies attempts to have White and Black capture each other.

Winning Conditions:
White Spies win by eliminating Black and Grey.
Black Spies win by having more of them than White and Grey.
Grey Spies win by having more of them than White and Black.