You're welcome.
One last thing. The Campaign is the main reason people buy Doom. You basically have to stop Hell's invasion of Mars, which in turn prevents Hell's invasion of Earth. There are many different types of demons and monsters you have to fight. Some are just fodder and some will try F*ck you up real bad!.
You also have sh*t loads of different types of weapons that you can use(which don't require reloading, just picking up ammo), such as:
Pistol(that you'll never use after the first level)
Shotgun(overpowered)
Super Shotgun(WAY OP)
Chaingun(minigun)
Chainsaw(NO NOT THE CHAINSAW!)
Heavy Assault rifle(this is a new weapon in the series)
Shock rifle(again new weapon)
Sniper rifle thing(i forgot the name, but it's a new weapon)
Gause cannon(new weapon, that's a giant laser cannon)
and more
And The Big F**king Gun 9000(aka BFG9000. This thing obliterates EVRYTHING! Use it on every boss you come across!)
So yeah tons of weapons and enemies/demons/monsters ready to murder you at any chance they get!