Pretty interesting concept, and nice original assets too. There are a couple issues with the mapping though. For one, the gray barrier around the edges is passable, but it sounds like it's not meant to be (since it allows you to reach the keycard without opening the gate, which TBH isn't that difficult the "normal" way). Also, the ending tile is inaccessible! Maybe you meant to put a gate there that opens when defeating the boss, but it's impossible to reach as is.