The level feels empty. There are no secrets, no ammo packs, no guns, only the map and the enemies (and some Spheres too).
You can only pick up guns from enemies. There are no ammo packs, so you mostly have to use the fists. The good thing is that there is a Berserk Pack at the start of the level, but still, it's not fun to just go and spam click with the fists, especially at the Cyberdemon fight!
Oh yeah, the Cyberdemon fight....nothing special about it. You just get an Invulnerability power-up and you just spam click with the fists until he dies. It is just boring.
In conclusion: great concept, but overall just empty.