MineCraft 1.3.2 Good Mob Mods

I can't seem to find any good mods that make the game harder or more diverse. I don't want any just like new trees or anything, I would like some suggestions to difficult mob mods hopefully run on Forge and be SMP.

I plan on getting Mo' Creatures, More Creeps & Weirdos and Weeping Angels when they update to 1.3.2 but maybe not Mo' Creatures with More Creeps & Weirdos because it would be way too much new stuff.