Hey Mate, hope you are doing well 🙂

Heh, Night watch. Loved that one and the sequel, Day Watch. Not sure if they ever finished the trilogy though as every time I search on the internet for “Twilight Watch” I am blessed with sparkly vampires…

Caveat that I don’t know much about SAoM, but for Mordheim monsters…

Ogres are the obvious ones to go for as they are the ‘big guy/heavy hitters’ for the Empire usually. If you are keen on tying uniforms in then Wargames Atlantic are bringing out a plastic box kit for Ogre Landsknechts some time this year, and I think MOM Miniatures do some as well if you are after something sooner. Or, we’ve all seen your ability with greenstuff, you are more than capable of adding slashed silk to an existing model I’m sure 🙂

Warhounds might be another easy to explain choice if you were after a pack/swarm type thing. Depending on where your warband is from might also help inform your choice – if they are from Middenheim might have a wolf pack/giant wolf mascot, Kislev you could lean into the bear aesthetic. Altdorf maybe they have a baby gryphon with them because ‘reasons’? (Maybe they captured it when it escaped from the private zoo of a rich noble in Mordheim and they are planning on selling it when they get back home for a tidy profit?) Marinberg could similarly have access to any ‘trainable’ monster from within the human lands (Araby Tilea, Estallia) due to naval trade, so lions, leopards panthers etc?

Another alternative is to go with whatever has been captured near Mordheim and can be restrained then unleashed in to combat as needed,, so anything that was stumbled across in the ruined city or en route/in the surrounding area. Maybe a brown bear/troll/warpstone mutated dire rabbit/giant spider on a chain. Or even a feral pit fighter/chaos warrior/bezerker?

If you were going to go for the elf/ogre/dwarf/halfling hireling option then assumedly any of them could have brought a monster with them as their mount/pet/camp guard/mascot? So then great eagles, war lions, drakes, stone or iron golems, yhetees, war goats, really cranky chicken (Knifegoose?).

Best of luck with the project! Sounds really exciting!