Creature sizes
Small = 75x75 pixels
Medium = 100x100 pixels
Large = 150x150 pixels
Huge = 200x200 pixels
Gargantuan = 250x250 pixels

New Sizes
Small = 40x40 pixels
Medium = 50x50 pixels
Large = 100x100 pixels
Huge = 150x150 pixels
Gargantuan = 200x200 pixels