I kinda associated each Evocation with one of the enemy types (Except for Zlonyth and the firstborn):
Elothu: Oddity (because he is humanoid like)
Farudon: Primal (this one should be obvious)
Ailtur: Machines (even if he does not look machine like in the least he is the only Evocation to use machine skills)
Ginyagu: Mystics (he looks kinda Whimsical and fantastical like many mystics)
Moror: Armored (He looks like a plant and the only plant enemy in the game besides the processing plants and the offshoots is a armored enemy the void tree)
Isanir: Creep (She is a giant centipede)
Chagora: Spectral (the weakest link since he does not use any ectoplasmic skills and uses phisical skills which very few spectral enemies use, on the other side he is kinda of ghost like in appearence)
Phritotch: Nightmare (one of the freakiest and most bizzarre designs out of all evocations, also specializes in eldritch damage)
Was any of that intentional?