Just wanted to say I tried pretty hard to break your level 4, but to no avail.
I'm really enjoying this so far, in spite of a few very minor grumbles. Very well done.
You didn't try hard enough. It IS possible to sequence break in level 4, and I did. Hitting that moving torch basically boils down to walking in and using the candle there until something happens, then grabbing the key. You can use that key to get into the second Scourge encounter, get the lens, and bring that into the first encounter. Using the lens, you can hit the Scourge, triggering a much harder version of the boss fight at the end of the level. It's basically an optional challenge for those who hate themselves. And it's fun. And well worth it when you finally walk into the boss room, the boss text appears, awkward pause, and then heart container drops from the ceiling.