Prey is full of nasty Typhon aliens aboard the Talos 1, you’ll need to scour the spaceship to find weapons and ammunition to take them down. One of the most powerful weapons in the game is the Q-Beam gun.
The Q-Beam fires a green, concentrated beam of energy full of negative particles. It can cut down even the most difficult enemies in no time, even if it is a little hard to manage in terms of reload speed, and inventory size. So how do you get the Q-Beam? You’ll need to perform some very specific tasks in the game.
First and foremost, the Q-Beam is located in the Beams and Waves Lab. To get into the Beams and Waves Lab, you’ll need to have repaired a hull breach earlier in the game during your mission that took you outside of Talos for the first time.
These are the basic steps you need to take. You’ll want to upgrade your repair functionality so that you can repair the hull breach that’ll give you access to the workshop. The hull breach that you need to fix will be right next to Dr. Calvino’s floating corpse that you’ll encounter on your spacewalk to find his key-card. You can always go back out and do it if you miss it on the first go round, or if you forgot to upgrade your repair capability before getting to this point in the story.
Once you do have the hull breach contained, you just need to go back to the lab. Once in the lab you’ll find a testing chamber that has the Q-Beam and a Phantom in a containment chamber. In front of that room there’s a console that will allow you to fire the gun to kill the Phantom. Press that button, and once the firing is complete, press the button below it to unlock the Q-Beam. Enter the testing chamber room and pick-up the weapon.
Once you do, you’ll find some ammunition for the weapon on the shelves beside it, and in the adjoining room.