Why not Midnight Bomys and Midnight Humans? Midnight Bomys terrorize people at midnight (player cannot control them) and the midnight humans turn into werewolves and attack with their midnight bomys!! Muha! I'm mad! Anyways... In daylight, they are average. They are a bit suspicious, though. If they stay out 1 hour in the sun they curl up in a ball then go mad. So they should stay in buildings during the day. A human could start exploding stuff!

Nah...

---------CUT---------------
 

---------------VERY LONG CUT OUT SCENE----------------------

Another idea:
Bomy players loose the control about themselves at midnight for an hour, they get controlled by an NPC who tracks other players and attacks them. The less AP the player has, the longer he stays controlled by the NPC. Saints don't get controlled.
And while they are controlled, they are much stronger than usual.

No...
 

They gain MAD powers at night, but in day they go crazy and an NPC controls them. If they get PKed, the NPC spirit comes out and tries to kill everyone. He steals someone's body then goes back to mass destruction. And there can be good ones. Eh?

....

Nocturnalness. Sounds good...
Vampiric bomys :D

That's nice someone left a comment that isn't rude on my idea!

*gives "Nice Person" award to Psyker*

Yay! :D

bomys cant be vampires... they dont have teef

WereBomys?
"There Bomys. There castle!"