If there is an even number of antitown factions at the end of setup creation, ignoring this role:
This role is town.
Half of all antitown factions can only perform actions/ have passive abilities during odd nights, and the other half perform actions/ have abilities only on even nights. Modify their roles as such. (This effects factional actions)
Then modify town power roles the same, making half only function on odd nights and the other half only on even nights. If there's an odd number of applicable roles, choose at random for the last one.
If there is an odd number of antitown factions at the end of setup creation, ignoring this role:
This role becomes a serial killer, then modify the setup as above described.