The challenge design on the castlevania levels you showcased looked great! Love the flowers and bouncing in rollie.
One thing i've thought before on making little backtracking loops like that (not just for this particular romhack - it's not meant to push a suggestion, but the showcase jogged my memory about a being in a similar situation) - to make the second loop-through different from the first, it may sometimes be a good idea to provide a modifier to the challenge or path so that it doesn't feels like a sisyphos hill. I think it doesn't matter as much if the challenge is easier or harder (one has the power to let the player through quicker, the other to engage the player in a new situation), just as long as it is somewhat different. Within castlevania constraints that might be another subweapon that is better suited to tackle those birds the second time or a multiplier tablet. Sometimes it's also possible to provide alternate routes using elevation as a unidirectional mechanism, though maybe not in the situation you showcased.
Edited: 03/19/2019
at 03:27 PM
by FrankenGraphics