Don’t worry if you can’t defeat it on your first try. She was meant to be a bonus fight for fun.
Also, Lilith will make a return in later encounters when you eventually return to that tower.
Hahaha I agree with you that the form shifting feels pokemon-ish.
More Feras will be show of course, but I guess out of the Party cast, the other feras helping you will be in the form of a skill.