The best of 90s FPS mixed in with modern concepts, all through an amazing campaign with level designs becomes crazier and crazier as you progress. There's some nice replayability too with different badges to get for each level, each demonstrating how beautifully crafted the levels are both to explore and find ever secret in, and to speedrun and blast your way through like a madman. There's also some legit horror moments in there, the endless mode is also very fun to play, the weapons are cool and all the references to your favorite games and nice touches.Overall a challenging masterpiece with a nice 6/8h campaign and more if you want to complete the hell out of it and find all there is to find.