We've been over catoblepas, and clearly you don't have malboros if you think spiracorn are strange. Which also likely counts out cactuars, mandrakes, and treants.

[is he counting off on his fingers while also rolling his eyes, ardyn why are you like this.]

In fact I'm willing to assume all the larger animal life we have is nonexistent, since combat ability doesn't sound common in your world. That counts out behemoths, Midgarsormr, and likely even dualhorns.