Not as good as the original Doom, but is a decent sequel.
Game play: Plays exactly like the original Doom, it utilizes the same game engine as the original, so I think the game play is very good.
Controls:
The controls are the same as the original, so no complaints there.
Challenge level:
Not too much different from the original, some strong enemies, some parts where I had troubles figuring out where to go, I even thought I got stuck, it turns out that I was at the end of the level so I beat that level.
Fun:
This game is kind of fun, but I don't think it was nearly as fun as the original, I don't know why, I just don't have as much fun with this game.
Overall, this game is a decent sequel, but it is by no means a classic, I give this game a 7/10.