Monstrous Physique — Metal Gear REX

Here’s the soundtrack for this week’s entry!

KD fan AJ asked me on our Discord if I would fulfill his request for a Monstrous Physique. I obliged, but when he asked me to stat up Big Boss from the Metal Gear Solid series, I just couldn’t. I tend to avoid humanoid characters mostly as those are more the realm of Iconic Design. And, while Big Boss can be a monster at times, he deserves to be statted up as an NPC. However, that request did inspire me to look at another iconic character from the series, the titular Metal Gear! While it’s technically not a character, I thought it was still worthy of its own post, so let’s take a look!

Metal Gear REX             CR 12
XP 19,200
N Huge construct (technological)
Init +8; Senses darkvision 120 ft., low-light vision, sense through (vision) 120 ft.; Perception +27
hp 200
EAC 26; KAC 28
Fort +12, Ref +12, Will +9
Defensive Abilities hardness 15, integrated weapons; Immunities construct immunities
Weaknesses array dependency
Speed 50 ft.
Melee kick +25 (6d4+20)
Ranged 30 mm rotary cannons +26 (4d8+12 B & P) or
anti-tank missile +26 (8d6+15 B & F)
Space 15 ft.; Reach 15 ft.
Offensive Abilities automatic reload
Str +8, Dex +5, Con —, Int –2, Wis +4, Cha +2
Skills Engineering +27
Languages Common
Other Abilities precise movement, unliving
Environment any
Organization solitary
Array Dependency (Ex) Metal Gear REX’s radome houses its primary antenna and sensor array. This array allows the pilot within the tank to see its surroundings with the cockpit closed. However, if the radome is destroyed, the sensory data feed becomes inoperative and requires manual operation by opening the cockpit. A creature can target the radome instead of REX itself. The radome has an EAC of 22 and a KAC of 28, uses Metal Gear REX’s saving throws, and has a total of 50 hit points. If the radome is destroyed, the pilot inside becomes exposed. For the purposes of these statistics, the pilot is assumed to have an EAC and KAC of 15 and 25 hit points.
Armaments (Ex) Metal Gear REX’s weapons include a set of gatling guns and a missile launcher. The cannons have a range of 120 feet. The missile launcher has a range of 240 feet, but is usable only once every 1d4 rounds.
Automatic Reload (Ex) Metal Gear REX reloads its weapons as part of the same action used to fire them.
Precise Movement (Ex) Metal Gear REX ignores the effects of difficult terrain. Metal Gear REX suffers the normal effects of difficult if its radome is destroyed (see above).

A Metal Gear REX with a damaged sensor array.

Metal Gear REX is a bipedal tank designed to fire nuclear warheads anywhere in the world. Its unique magnetic rail gun allows the tank to fire the gun without a propellant trail or a lunch flare, preventing it from giving away its launch position like a traditional ballistic missile would. In addition to its rail gun, REX also features a built-in set of rotary cannons and missile launcher, allowing it to deal with targets at closer ranges. When all else fails, REX is capable of stomping on its targets with its powerful legs. The powerful frame of REX is reminiscent of a the Tyrannosaurus rex, thus earning it its name. REX has a flaw in its operation in that it relies entirely on its sensory systems housed within its radome. Without these systems, the pilot must leave the cockpit open to manually operate the vehicle. This flaw appears to have been placed intentionally. Whether due to its flaw or for other reasons, REX never entered a mass production state, but did inspire other bipedal tanks that improved upon its systems.

That’s it for this week! If you end up introducing Metal Gear REX into your game or you have any request for a future Monstrous Physique, please drop me a line at

Luis Loza

Luis Loza is a developer at Paizo, working on the Pathfinder Lost Omens line and formerly on Campaign Setting and Player Companion lines. He's done freelance for Paizo Inc, Legendary Games, Rogue Genius Games, and more third-party publishers. His hobbies include gaming both tabletop and video, making jokes, obsessing over time travel, taking naps with Nova his cat, and walks with his wife. He is eternally plagued with a hunger for tacos. Consider checking his material on his Patreon at