The contrasting object line colors would usually be distracting but the shade you picked really plays well against each other so well that when they transform, you can't even tell where it really takes place.
Makes me think of BeastofOblivion's creatures (I can't remember the user name exactly nor the creature's names... Locks, I think?).
Except... these don't flow? Not the pose, but the "design" of the creatures. It's very... flat, boring... they don't merge together to make one, they make two pushed together. Or rather in this picture, four beings.
I'm trying to put it into words. Even if it was just for fun, it feels awkward and uncreative.