FIGHT!

Who wins, one-on-one:

(EDIT: it's in a space opera, the unicorns are GM horses, the raptors are modified birds. Boring, I know: no magic, no rainbows! But also starships and robots …)

Unicorns
40.5%
Utahraptor (like a big velociraptor)
59.5%
Poll ended at .
@cstross we voted unicorns because it feels like the body design of utahraptors makes more sense for group hunting
@ireneista @cstross gotta admit I'm thinking "what if the unicorn misses?" there, though - neither's looking great, but the utahraptor actually benefits from staying side-to-side
@ireneista @cstross ...the unicorn's going to be plain bigger, mind

@ireneista @cstross I reckon it comes down to whether the raptor can place its forearms/wings in a way that stops the unicorn picking up speed to get away and come back for another pass: if it can in principle, you've got a messy opening stage but things get determined pretty quickly once the unicorn's caught.

If not, how fast can the utahraptor step to the side and turn inwards?...

@flippac @cstross you also have to remember, utahraptors are built for speed, for sure, but the unicorn's eyes and visual cortex reflect over a hundred million years of evolutionary improvement that the utahraptor doesn't benefit from. seriously, dino eyes have a ton of problems. if it turns into an extended battle, that could prove critical.
@ireneista @cstross If it turns into an extended jousting contest, absolutely - I'm not sure grappling necessarily got better rather than more specialised though, and if the contest is "spike the raptor enough" vs "grab hind leg" then it doesn't help the unicorn that the offensive and defensive motions are mostly the same thing: scratching up the raptor's flank isn't so easy if the raptor's already hauling it for a grab

@flippac @ireneista Okay, so let me mix it up a bit:

The unicorn is harnessed to a light two-wheeled carriage (like a curricle or a gig), made with modern materials. Two humans on board, one driver, one passenger. (They may be armed.)

The raptor is trained for riding and is saddled up: it may be gagged (but beware those raptorial claws!). One rider, also armed.

Weapons are most likely black-powder pistols.

Anyway: both animals are constrained! And black powder weapons won't help much.

@cstross @ireneista How far out do the humans see each other, how much do they trust their steeds' training and how daft are they?
@flippac @cstross all interesting fights start with human folly, so let's assume the humans don't think to take aim until the animals are charging
@ireneista @cstross do the animals actually have cause to charge until the humans open fire?
@flippac @ireneista Yes: it's a chase, humans in unicorn-carriage are fleeing, rider on raptor is trying to arrest (not kill) them.
@cstross @ireneista Assuming the unicorn has the bad attitude, it fake-bolts, the carriage gets the shit knocked out of it briefly then the real fight begins with the unicorn far enough to give it an advantage as it turns around?
@cstross @ireneista (actual chase-into-fight is boring at best and while the unicorn's tied to that carriage it's either capable of outrunning the raptor or not: if not, it's raptor food because the raptor is in control of the approach whatever happens to the rider - we might get "raptor wins, unicorn's people win against rider, raptor decides unicorn is enough dinner" for example)
@cstross @ireneista the rider is seriously ill-equipped for an arrest unless there's personal armour in play or a better weapon for a grounded fight FWIW
@flippac @cstross yeah you're right