nocturnal npc behavior

[Aramara Meibi]

i was reading through this:

http://www.atomicblue.org/tribes.htm

and was really impressed by the idea, but I'd like to see an addition to it, and that is separate nocturnal behavior for NPCs. For example:

A specific mob type grows more aggressive or defensive at night.
Mobs that only appear at night.
Mobs that are more active during the day and nest at night and vice versa

that's all i got for now. list more if you got em.

[Earowo]

What chores the npc would be doing would definitely depend on time of day, such as harvesting, eating, standing on guard, ect.