From playing up to boss, never managed to kill it hahah, I had no issues in terms of game play mechanics mind you it was hard for a beginner like me =D , they worked with no glitching or frame rate drop for 90% of it, I got to the boss fight and I noticed a there was some slow down of the frames not lag but like a -15 of everything monsters slowed down to a walking pace when a walked to edge of the ring it speed up again so I'm not sure if it was intended, other wise I really enjoyed it, it has replay value nice work.
Lastly the world it self I started to wonder what the people were doing in the grave yard area and what was happening in the world, so that was interesting also.