Upon spotting the player, the Gunner fires bursts of several nails from its nailgun, with a brief pause between bursts. The nails are quite accurate, but travel slow enough to dodge if the player is far away or moves quickly enough. The Gunner also occasionally lobs a bouncing grenade at the player using its grenade launcher. The Gunner always signals that it's about to launch a grenade by cocking its arm-cannon before firing. The Gunner can stalk back and forth while firing or walk forward to pursue the player, but its speed is relatively slow and it is unable to run. Gunners in Quake 4 are not as threatening as they were in Quake 2, however as a Strogg support unit, they are armed to the teeth and can cause player trouble if underestimated.
Due to their below average speed, Gunners are fairly defensive and tend to guard rooms, areas or corridors instead of chasing the player. Gunners are usually encountered one at a time, often accompanied by a squad of Guards or Tactical Strogg. They are reasonably common throughout the game, with a handful appearing in most levels.
Like the Berserker and Iron Maiden, the Gunner is a mid-level Strogg unit, tougher than "cannon fodder" Guard or Tactical Strogg units, but not as strong as the heavy units such as the Gladiator or Light Tank. They have about 2.5 times as much health as a Tactical Strogg, and it takes about 20-30 Machine Gun bullets, 3 full Shotgun blasts, or 3 direct Grenade Launcher or Rocket Launcher hits to kill one.
- The Gunner is a fairly large target with below average speed, and less maneuverable than most other stroggs, so landing shots should be easy. Although fairly tough, the Gunner's durability is reasonable enough for the machine gun to still be effective against it. At close range the shotgun also works very well, as a direct blast has a very good chance of causing the Gunner to recoil, briefly stunning it and preventing it from attacking, giving you time to take aim and fire. Heavier weapons such as the Nailgun (with the homing nail upgrade is best) and Rocket Launcher are also highly effective at longer distances, Railgun users can take them out at long distances, its scope can be used to help if you have aiming problems.
- Avoiding the Gunner's attacks can be tricky, as it fires a near-constant stream of nails as soon as it sees you. When you see it, try to get near an area that has good cover. When the Gunner sees you, take a few shots, then hide and let the nail stream fly by you. Repeat until it tosses a grenade or two at you. When it does, run to another spot while firing it at. Repeat this until it's dead. The Gunner has an attack delay when first encountered, so you can take the first shot by aiming at head, this is not easy but if you can do that, you can cause some good damage to it before it reacts. After that it will attack on sight, but the attack will stop after few barrage of nails and grenades if the player is not seen.
- Keeping distance makes the tactic explained above much easier: you'll both have more time to avoid the nails, and the Gunner's grenades won't travel far enough to hit you, you still need to retreat if the grenade is too close though. If you have already cleared the room from other enemies, you can save up ammo and shoot charged-up blaster shots, especially as you can charge your blaster while in cover, as the stream of nails passes by.
- In some cases, you might not be able to find appropriate hiding places. In this case, try to circle-strafe the Gunner if he's on the same level you're on on. If not, try to shoot him while constantly moving and strafing. If he launches the grenades at you, don't hesitate and strike before he use his nailgun against you. Sometimes the Gunner will attack from above, take out the Gunner quickly before it does too much damage. If he is below, deal with closer threat first. I f you don't have any room to move, use the heavier weapon to kill it quickly.
- With other enemies, the Gunner should be taken out after killing the cannon-fodder in a group. While it can be difficult to avoid nails while taking out cannon-fodder, it's much better than having to avoid nails while getting shot at by every other enemy. Since the Gunner is somewhat slower and more defensive than Guards or Tactical Strogg, a good strategy is to backtrack to a previously cleared room; the cannon fodder should follow you, while the Gunner will hang back and tend to stay inside the original room it was encountered in and wait for you. Even though in some rare cases it will follow you, but their slow speed means they need some time to reach you.
- If you encounter more than one Gunner, try to take out one at a time; in escort situations, you may see Gunners appear among the Berserkers, you should focus on the Gunner immediately after the Berserkers are dead.