Human Peter already said in an interview that there won't be a Human creature. After that there really haven't been any screenshots of the Human creature, but as a christmas present we got a shot where a human male is fighting. If you want to know how powerful the human creature is, go to the zoo and challenge a bear. Wolves are strong and fast and good fighters. Lion Aggressive creature.
Lions are strong and pretty fast and they are good fighters.
Zebra Zebras are much like horses. Passive and strong, but it doesn't have so fast moves. It runs really fast though. I would say bears are almost neutral creatures. They might be more at the aggressive side though.