The Mecha-Arachnoid is a large, purple scorpion with miniguns for claws and a laser gun on it's tail. It was created from a scorpion Mental had found in Ancient Egypt. Normally, the Mecha-Arachnoid will fire miniguns, but will occasionally switch to firing a powerful blue laser from its tail. The bullets from the minigun have infinite range, but the miniguns themselves will become less accurate the farther away the target is from the Mecha-Arachnoid. If someone gets close to it, it will smack the target from with the side of its miniguns.
The Mecha-Arachnoid almost never moves, mostly likely to assure that it'll keep firing it's miniguns.
Mecha-Arachnoids are uncommon throughout the game. They are somewhat common in the later parts of the Ancient Rome chapter, but otherwise, don't appear very often.
- Use cover whenever possible. The Mecha-Arachnoid fires insta-hit bullets from it's guns, and these can only be avoided by using cover.
- If there is little to no cover, getting away from the Mecha-Arachnoid makes its miniguns less accurate than at close range, which reduces the amount of damage the player will take from it.
- When the Mecha-Arachnoid moves it's tail forwards, start strafing to one side. This is a sign that the Mecha-Arachnoid is about to fire a laser from it's tail.
- The XPML4000 Rocket Launcher is very effective against the Mecha-Arachnoid. It's rockets can do a good amount of damage per quickly, and enough rockets can be fired by holding down the fire button that the volley of rockets will kill the Mecha-Arachnoid before it can do too much damage.
- The XM4000 Minigun also works if there are other enemies nearby, as it lets the player clear out any nearby enemies while attacking the Mecha-Arachnoid. However, the XM4000 does less damage to the Mecha-Arachnoid than the Rocket Launcher does, so the player should switch to it when nearby enemies have been cleared out.
- At close range, the Double Barrel Shotgun works in a pinch. Each shot is about as powerful as a rocket if all of the pellets connect. Because of the Mecha-Arachnoid's size, they will. However, being at the Double-Barrel Shotgun's effective range puts the player close to the Mecha-Arachnoid's miniguns, which can do a lot of damage. Cover is essential if the player intents on using it to kill the Mecha-Arachnoid, or otherwise the player will take a lot of damage trying to kill it. Otherwise, the player should get away from it and use something else, like the Rocket Launcher.
- Long-range Mecha-Arachnoids should be dealt with by using the RAPTOR Sniper Rifle. One zoomed in shot can inflict a significant amount of damage per hit, making it very effective against it.
- When paired with other enemies, the Mecha-Arachnoid is a high-priority threat. It's miniguns can inflict a good amount of damage at any range, which allows it to slowly drain the player's health while the player is dealing with other enemies. Getting rid of it will give the player's health and allow the player to better focus on other enemies.
- The Mecha-Arachnoid is extremely identical to the Centroid from the Quake expansion pack, Scourge of Armagon.