Illustrations, 2D art and scribbles
Heman and She-Ra redesigns
As the transformation was all about the "power", I thought about giving them invincible energy forms, instead of a loincloth. I also tied them to Skeletor's back story, as he was mangled while trying to harness this power for himself. I also tried to address the question of "why were Adam and Adora chosen?"
I always liked it when he turned his arms to flamethrowers or laser cannons, And he could change his entire form - one time he turned into a rocket! So cool!
So I just took it a few steps forward, with blades and monster parts... seemed reasonable.
Leeches and Lampreys are alien as is, but I also imagined him as a lumbering giant, always hungry, that almost nothing phases... slow but unstoppable. I also wanted him to be able to talk, so I envisioned an inner mouth just for that.
King Hiss looked cool! But I thought a huge, hydra like creatures, might be even better... eventually I went with the concept of a "Rat King" but with snakes (check the freaky phenomena here - https://en.wikipedia.org/wiki/Rat_king).