- Swann: I'm here because there seems to be some very serious problems.
- Betruger: [condescending] Oh really? Do I need to remind you of the groundbreaking work we're doing here?
- Swann: No. But I've been authorized by the board to look at everything.
- Betruger: [scathing] The board authorized you? Hmmm. The board doesn't know the first thing about science. All they want is something to make them more money, some product... Don't worry, they'll get their product.
- Swann: After how many accidents? Tell me, Dr. Betruger, why are so many workers spooked, complaining, requesting transfers off Mars?
- Betruger: They simply can't handle life here. They're exhausted and overworked. If I had a larger, more competent staff, and bigger budget, even these few accidents could have been avoided.
- Swann: I'm afraid you'll get nothing more until my report is filed with the board. I will need full access, Dr. Betruger, Delta included. I won't have any difficulties doing that, will I?
- Betruger: Only if you get lost, Swann. Just stay out of my way. Amazing things will happen here soon. You just wait.
- Swann: I can't believe it's come to this. I didn't want to come here.
- Campbell: He left you no choice.
- Swann: True, but this is the last time. I'm tired of running damage control every time he makes a mess.
- Campbell: Right, you're the control. And if that fails, I'm the damage.
- Swann: Whatever it takes, Bertruger is going to start doing things OUR way.
- Campbell: Whatever you say, Counselor.
- Soul Cube: [after it becomes fully charged] Use us!
- Derek Wayland: [in an email to Walter Connors] I wanted to personally thank you for your latest modification proposal for the dilation matrix. The boys here at CPU have crunched your numbers and after some deliberation we've agreed that this is the most fantastically bogus theory that we've ever seen. If you are remotely interested in not getting your gnome-loving dragon-slaying power-leveling ass fired, I'd suggest you lay off the role-playing and learn some basic math. Good luck on your next review.
- Marine #1: [Last lines] What about Dr. Bertruger?
- Marine #2: He's no where to be found, sir.
- Betruger: [Bertruger is revealed as a monster in hell, it's screaming]
- Sarge: [talks to DoomGuy after the cutscene of the members of Bravo Team being killed] Marine! Bravo Team is down, their operational status is unknown. They were carrying a military transmission card, it's vital that you retrieve that card as it contains encoded data needed to send a distress signal to the fleet. You're the last hope to get reinforcements! Find that card, and find it fast!
- Sarge: [as the boss Sabaoth] Assholes and Elbows!
- Sarge: [comes on the radio after DoomGuy enters an airlock and opens the other end] Marine, get your ass to the Communications facility as quickly as possible! You gotta get that message to the fleet!
- Sarge: [upon DoomGuy entering the Communications level] Marine, have you reached the Communications facility yet? You've gotta get that message to the fleet now! And watch out for Campbell and Swann, those UAC suits don't give a damn about what happens to any of us. Now get a move on!
- HP Coordinates: [in an email you receive after scoring 25,000 points on Super Turbo Turkey Puncher 3] Congratulations! You set a new high score in Super Turbo Turkey Puncher 3! Your parents can rest easier knowing they have raised another shining example of humanity. Due to the incredible amount of time you wasted punching poor defenseless turkeys, your vacation time has been docked two days. Have a nice day.
- Doom Guy: [Upon seeing the Cyberdemon] Fuuuuuuuuuu...