Hello~
I like the Art in this game, It's Beautiful. The Music sounds Nice and Spoopy and fits with the theme of the Game nicely. The Idea of Spirit Mode allowing the Player to interact with Invisible Objects is Clever. The Skull Mask and Sprite change when entering Spirit Mode is pretty Cool too.
I decide to go into the Game Blind and didn't know that you guys post the solution for the Tree Map. I didn't realize the Metal Bar that was blocking the Pump disappear so i tried to Jump into the Slope manually Instead. but I eventualy realize it and Interact with Pump. Maybe you guys should Zoom the Camera into the Unlocked Metal Bar? (Or maybe I'm just Stupid Haha :D )
The Second and Third Stage is nice. The Camera Zoom in to indicate what change so it helps the Player to know and I also like the Platforming on those Stage.
Overall I think this is a Pretty nice Demo :D
(Sorry for my Bad English. It's not my Native Language XD )