When I looked at this c.1916 picture of Elasmotherium, my first thought was, “Fuck, it’s a really-truly unicorn!” (More recent pictures look more like woolly rhinos.)

The artist, Heinrich Harder, made a lot of pictures of prehistoric animals. Arsinoitherium had a particularly badass head, but as a mostly aquatic swamp dweller it can’t be a candidate, rather to my regret.

Elasmotherium may have survived into historic times. 10th century traveller and writer Ibn Fadlan describes an animal that matches Elasmotherium’s description, and gives this colourful account of its behaviour: “Whenever it sees a rider, it approaches and if the rider has a fast horse, the horse tries to escape by running fast, and if the beast overtakes them, it picks the rider out of the saddle with its horn, and tosses him in the air, and meets him with the point of the horn, and continues doing so until the rider dies. But it will not harm or hurt the horse in any way or manner.”

Glyptodon and Doedicurus match up with Kirby’s suggestion of an armadillo. Glyptodon looks rather round and slippery for riding on, but Doedicurus had a dip behind a hump in the shell where a saddle might go — and the hump was possibly a fat store like a camel’s. It also had a wickedly spiked tail. I can imagine it surviving a bumpy fall, which would be a bonus.

Waiving the issue of domesticability (I think that already got waived with the centipede), it comes down to a bit of a dance between ambience and narrative ideas. While I want to avoid a big-lipped alligator moment, I’d also really like to have a beast that can do more than break its legs/neck when it falls.

No, I don’t know why I’m getting so obsessed with this. Wait, yes I do. I’m not sure how to write the scene after the one I’ve nearly finished, and research is the noblest form of procrastination. Gulp.