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Looks like a taurga to me

This could be a taurg!

  • Taurga (plural) taurg (singular) of Canea - huge, stubborn, bad-tempered bull-like beasts, used for Canim calvary and as beasts of burden. Unsuited to sea voyages.
By the end of the third day, the taurg Tavi was riding had only tried to kill him twice—since lunchtime. By the standards of Canim cavalry, the beast was behaving admirably. The taurg most closely resembled a bull, Tavi had decided. It was a bit bigger, and considerably humpier about the shoulders. Its rear quarters were much more heavily muscled, as well, and its legs were longer, springier, more in proportion to a hare’s than to anything so large as it was. The beast was covered with thick, curly fur that ranged from deep grey on its blunt muzzle to blue-black on its shoulders and haunches. Its neck was thick, its head was rather tiny, and its brow was half-encircled by a massive, bony ridge that was capable, so the Canim claimed, of smashing through stone walls. Its eyes were tiny and pink and hostile, its wide nostrils drooled a constant stream of slobbery mucus, and its cloven hooves struck at a speed that rivaled that of any warhorse in Alera—and hit with several times the power. (Princeps' Fury chapter 16)

Taurga are ridden by Canim warriors and are fearsome in battle; much faster than a horse, bigger than an elephant, and stronger than a rhino.

A taurg is susceptible to sea sickness, so they could not be brought to Alera when the Canim, under Nasaug, invaded Alera.