Having clocked the game I feel I can now write a informed review. An instant Doom classic that goes back to it's roots. Very fast paced frantic combat in nasty environments against viscous monsters . Big guns and unrelentingly aggressive. Lighting is great and very engaging environments and arenas. If you like your FPS games this is a must play with multiple weapon and armor up grades and things to find in the darkest hardest to reach corners. I found it very enjoyable and highly recommend.