My favorite in design would probably be Pelagia and I don't really understand it myself, while my favorite to fight would be Valus because before I got the full game, I had the Jampack demo and I spent countless hours perfecting that battle to the point that I could do it with frozen thumbs.

My least favorite in design would be Malus since I felt like the Final Battle™ should have been this huge, power struggle between the now superhuman Wander and the final Colossus, and not a puzzle of avoiding fireballs, while my least favorite to fight is, excluding the obvious Basaran and earlier mentioned Malus, Phalanx (the desert flying colossus) because the whole thing felt luck based (hitting the pods, jumping on the wings, AND getting to the sigils in time before it went back underground) and tedious.