This is really just someone's Doom WAD with a fresh coat of paint. It doesn't do anything mechanically interesting. There's nothing more or less to be said about it.
This might be just a bit too short (2-3 hours) for the price, but I guess it's better than being bloated. I don't want to repeat too much of what I said here...There are more unique enemies, the levels are great, with maybe just one of them being a drag, and the developer actually makes good use of the scythe-start. Some of these levels are actually very open, letting you choose your own path each time you play the map. Unfortunately, all the weapons you saw in the demo will be the only ones you find in the game. I also wasn't too hot on the treasures (think treasure goblin) here and would have much preferred the standard secrets for some variety, especially on the levels that have no treasures.