I believe it was called Ironcat, and it might have been uploaded by a user called 77 Stelaris but I'm not 100% certain, I think they might be Chinese. There were a couple versions floating around being publicly available, but they all seem to have been taken down or removed at some point.
I really loved this avatar and would love to have it back, so if anyone thinks they have the files or such for it I would much appreciate it!

Edit: I don't think this is an Ironcat avatar, but I do think it's something similar. I managed to find out some of the assets used too so if anyone can find some of the other assets (wings & halo, glasses, suit, reflective bow) that would laso be helpful.

Here are some pictures of some versions of it