WotBS Help with tying in a backstory monster

[Tolamaker]

One of my player's backstory involves a great monster that wiped out his company of Dasseni soldiers at the Ostalin border, and he's the only survivor. He's left what the monster was to me (PTSD blocking out his memories), and I'm trying to think where I could possibly find an existing monster that could be the culprit. I've read the synopsis of the whole adventure, and read halfway through adventure #5 in-detail, and I'm not sure if I've found a monster that's a good fit. I'd probably want to tie it into a later adventure too, just so he doesn't feel like his story is done halfway through.

It could always be a trillith, but I don't want to make Hunger for example, and find out there's one named Hunger later on that I have to work around. Though if there is one, maybe it will be a good fit.

I could make up my own creature if I have to, but I'm reaching out to you all so I can be lazy properly tie my player's narrative the to campaign.

 

[RangerWickett]

Pilus has his biomancy laboratory, so it could be some horrible custom creation. You could make something new, or use . . . I think there was some sort of dragon/manticore hybrid guarding the Valley of Storms. But we wrote that one 14 years ago, so I don't have the clearest recollection.

 

[Tolamaker]

Pilus has his biomancy laboratory, so it could be some horrible custom creation. You could make something new, or use . . . I think there was some sort of dragon/manticore hybrid guarding the Valley of Storms. But we wrote that one 14 years ago, so I don't have the clearest recollection.

Ooh, I like that. The manticore/dragon sounds fun, or the chance to mash two other monsters. Thanks!