Well it follows a similar idea to Bard's; instead of holding the most revenue at the end of the game it's whomever has the highest killcount
The difference was, if I'm not mistaken, you could still get eliminated during the day in Bards which is a core part of mafia and actually required by our rules. So the game needs to have players dying off during the day or at the very least, to have that possible.
Given the idea is zombie themed... you could have a set number of people and one zombie. During the day everyone votes to eliminate who they think the zombie is. During the night the zombie can infect a player, turning them into a zombie. The zombies win if they take over a set majority of players, like say 2/3rds or so, and town wins if they kill off all the zombies. Since the concept favors the zombies a bit you could have power roles that don't transfer over if someone gets zombified, and have just the first zombie able to bite and recruit someone.
Now I'm a complete novice at mafia planning, but since the film (I don't really count the others as they kinda suck) had a zombie infectee the concept might work. But this probably needs a lot of refinement. ><
R.I.P Isaac J. Southerland Jr.
1946 - 2017