So after a (brief) search through this forum, I can't find anything mentioning hoofed creatures, such as horses, deer, cows, goats, etc. My suggestion (which will also be brief because it's past 2 am over here) is split into two:
1: Accessories (aka An Easier Solution)
The simplest thing to do would be to introduce a handful of ear/tail sprites for equine races. We already have cow and horse tails attached to the taur forms for each, so it shouldn't be too hard to come up with a set of sprites for various hoofed creatures and add them to the game as selectable ears and tails.
2: A Race (aka A Thorough But Complex Solution)
It'd be kinda neat to have a horse-like species, especially if we're already going so far as to add foxes and fennecs to our game. I haven't thought up too much for these guys so far as racial differences go, but here's a few ideas that can be built on:
Hoofed feet - Having hooves is a blessing and a curse. Walking over glass would be fairly inconsequential, so that's a plus. But modern footwear isn't designed for hoofed feet, so good luck putting on magboots and such. To balance, perhaps give them a slight speed boost so their barefoot speed is equal to (or dare I suggest it, marginally greater than) regular walking speed with shoes?
Slower nutrient loss - A handful of hoofed creatures (namely cows, deer and goats) are known for having four stomachs, consisting of the Rumen (a holding chamber), the Reticulum (where bacteria break down plant matter), the Omasum (where liquids are absorbed) and the Abomasum (where regular digestion occurs). Thanks to having so many compartments on the way through, they could conceivably either gain a larger benefit from each meal, or take longer to process each meal, taking longer for nutriment to deplete, but also taking longer for reagents to metabolise.
Hoofed Fingers - This is me throwing ideas at the wall here and I honestly don't expect this one to get through, but I figured I'd suggest it anyway. Having hardened fingers, they could have natural insulation (only SLIGHT protection) against electric shocks. Alternatively (or perhaps additionally), they could leave no fingerprints. I honestly can't think of a way to balance either of these though, and they're fairly powerful.
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So yeah! Take these as you will, I'd love to see what you guys think about the suggestions I've made here, and if you can think of other racial abilities, perhaps?