Add a Goat. Either rid-able or just as another beast. For a Beast: have it as a charging animal that does strong bashing/knock-back attack, but is a lot faster than a Bear. Basically the strength and similar attack of a Bear, with the speed and agility of a Goblin.
Here is an image I got off of Google Images:
Another possible animal is a Warg. It wouldn't be as strong as the Goat, but there would be more of them, and possibly even ridden by Goblins.
From Lord of the Rings:
The only problem I see with adding these animals is that they would get stuck in the walls in Ruins (unless they can make them smarter), so they might be more suited for the Desert map.
Horses could also be added like the other thread Yanihero1 said in the other thread.
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