I would love to see more creatures in this game. Here are some I think would be cool and really add more variety in the game...

Barren/Deserts:

Giant Scorpions (would love to see these, clash of the titans anyone?), Sand Worms, Giant Ants, Cyclopse

Swamps:

Giant Snakes and other reptiles such as a Crocodile

Forests:

Ghosts, Giant Caterpillas and Centipeades, Panthers or other big cats, zombies

Snow:

Ice Giant, umm help me out with the snow creatures

Water (would love to see this):

How about a giant octopus or squid or other sea monster that can attack your transport?

Anywhere creatures:

Skeletons (these should absolutely be in), Giants (ogre is similar though, maybe these can be even bigger), Bone Dragon, Rats, Wearwolf, Grim Reaper, Minotaur

Well, these are all I can think of for now. COME ON PEOPLE ADD SOME MORE! [e digicons]|-)[/e] Ideas seem like they can be endless with this game as far as creature types go. How about some cool D&D style creatures. Heck even check the creatures over at Spore, that gives really good ideas.