The Common Aludran Reptiloid is a medium-sized four-handed bipedal reptilian creature that has agreed to work for Mental, in exchange for magical powers. In early levels of The First Encounter, it spawns a short distance away from the player, while as the game progresses, it spawns far away, such as on top of pillars, columns, roofs, and so on, to snipe the player.
They are more mobile in The First Encounter, compared to The Second Encounter, where they are usually stationary.
Reptiloids start out from the Valley of the Kings, where they are rather uncommon enemies, but in the following levels, more and more of them appear, until they become common. There are lots of Common Aludran Reptiloids in The Second Encounter as well, from the first level to the final level. Most of them appear at long distances and are usually located on rooftops, ledges, pillars and other elevated places.
The Common Aludran Reptiloid has two attacks: conjuring a magic energy ball that will home in on the player, and punching the player at close range. The homing energy ball will try to hit the player, and if it misses, it will turn around and try again. This projectile is destructible and will not be destroyed upon impacting with a surface or wall. The Common Aludran Reptiloid will deliver a powerful punch to the player if he/she gets too close.
- The minigun and lasergun are good weapons against a group of Commons, as not only do these guns kill them relatively quickly but also help to shoot down fireballs as well.
- The rocket launcher is also a good weapon for destroying Reptiloids from close-to-middle range. It's not much reliable for longer distances, as the rocket may impact with the projectile instead. This has a smaller chance of happening, usually for closer distances.
- The RAPTOR sniper rifle can dispatch a few Reptiloids easily, as 2 shots (3 shots in classic) are enough to bring them down.
- The SBC cannon can be used as a last resort against Commons, but it is not recommended.
- With other enemies, common Aludran Reptiloids should be high-priority targets at least in higher difficulties as its projectiles can become dangerous if left unchecked.
- Alduran Reptiloid Highlander — larger and more dangerous variant of the Aludran Reptiloid.
- Albino Cyclops — the common's Serious Sam 2 counterpart.