Solving the puzzle to the door!!
To proceed through the door with the puzzle element to it, after the long battle with the ape boss, you will need to do the following:
Slash upwards on the first red circle, leaving the second circle as a miss hit, then slash upwards again for the third circle, leaving the fourth one as a miss, and lastly slashing upwards yet again for the fifth circle to solve the puzzle.
Hopefully that\'ll help those that are indeed stuck on that door.