Mod recommendation that could fit a frozen wasteland theme

I want to create a modded hardcore server around the thematic of a frozen wasteland, and I wanted mod recommendations for 1.20 that could fit the theme. the idea is that every a few days the difficulty of the server will increase, so I'll also appreciate if you have any mods ideas that could be added on more advanced stages of the server (for example, I'm gonna add a wendigo mod after a few days the server starts).
I'm mostly looking foward to frozen mobs mods, if they add other mobs besides the frozen ones isn't a problem, but any other mod related is very appreciated, thanks!