I know all code/art/assets need to made during the jam, but what about animations for 3D art? Can we use something like Mixamo for this purpose? Or do we need to create animations as well?

bomp

It says in the rules that no pre-made assets are allowed - including other sources

so I guess the answer is no?^^

I am interested in helping you NightEmber. I am a CGI generalist. I use Maya, Substance, Houdini, Zbrush and Unity