The REV9 Powered Armor is the first powered armor unit encountered by the Point Man in F.E.A.R. 3. Unlike the REV6 Powered Armor, this one is a more advanced version, utilizing more powerful, slower firing heavy autocannons instead of rapid-fire Gatling guns. It also replaces the missile pods of older models with a powerful ray gun, and it can sprint, unlike its heavier counterpart.
Paxton Fettel must possess a body to pilot this. It is also the first Powered Armor that the player is able to pilot.
The REV9 is first encountered in Interval 04, piloted by both enemies and the player. They are smaller and more lightly armored than the Enhanced Power Armor. Like the heavier EPA, the REV9 does contain automatic self-repair systems, as when the player stays out of the line of fire for a short time, the REV9 will repair itself. But if the armor is critically damaged, the pilot will be automatically ejected before the armor explodes, unlike the EPA, which will eject the pilot and then repair itself.
In addition to its laser and cannons, the REV9 also has two melee attacks; first, it can swing its right arm, and the second is it brings up both arms and slams them down. When deployed, the REV9 uses much the same mechanism as the REV6 seen in F.E.A.R. 2: Project Origin, except that the sphere that contains the Power Armor explodes in mid-air, and the REV9 lands via the rockets underneath its feet.
These are fought in Intervals 04, 05, 06 and the Contractions multiplayer map, "Mechanized Invasion." The player can pilot them in Intervals 04, 07 and the "Mechanized Invasion" Contractions map. The encounter in Interval 05 is the only time that the player must fight the REV9 on foot.
The REV9 Powered Armor is one of the toughest enemies the Point Man and Paxton Fettel will face, especially in the higher difficulties, as it is very deadly to face without piloting another Power Armor. Using Zap grenades is highly recommended, as they will stun and lock the REV9 in place, allowing for free potshots. An Arc Beam is also a prime weapon to utilize, but if one isn't available, frag grenades and other high-damage weapons, such as a G3A3 Assault Rifle or S-HV Penetrator will make the difference between life or death.
- The REV9 is most likely a follow-up of the program that produced the REV6 Powered Armors, as they are both controlled by the user in the same manner.
- While the REV9 piloted by the player can use melee attacks, enemy REV9s will never use melee attacks against the player if they are piloting another Power Armor. However, if they aren't using another Power Armor, enemy REV9s will attempt to melee the player if they get into melee range.
- For an unknown reason, during Interval 04, a broken REV9 (with its left cannon, right arm and leg missing) can be seen, despite the fact that it is supposed to self-destruct after receiving massive damage. It can be assumed that the self-destruct system is triggered when the REV9 power supply unit is destroyed or too heavily damaged.
- When enemy REV9s use their mounted laser, the beam noticeably sways side-to-side, however, the REV9s that the player use fire the laser straight, without the side-to-side sway.
- When using the "sprint" feature on the REV9, the player isn't "sprinting" in reality, but is actually using rocket thrusters beneath the REV9's feet to move forward faster. These are also the same rockets that are used by REV9s when they are deployed in Interval 05 and 06. Like the player's REV9, enemy REV9s can also sprint if the player moves far enough away from them.
- The Point Man cannot use Slow-Mo when piloting a REV9. The same goes for the Enhanced Power Armor.
- When the REV9 is deployed against the player in Interval 05, if the player watches closely when the sphere containing the REV9 breaks open before it lands on the outer wall of the apartment complex, there is a brief burst of machine gun fire coming from the sphere. As the REV9's ranged weapons consist of only the ray gun and cannons, it could be assumed that the launch pods themselves are equipped with a machine gun in order to defend the pod from being shot out of the sky by ground forces.