Alien Runner
Runners are the most common enemy in the game, being born out of the local wildlife around Pala Station.
Runners are based on their Alien 3 counterpart, the famous Dog Alien, or "The Dragon", they share their counterpart's aggression and speed, and sound quite similar too.
Runners work as the basic fodder unit from the Alien faction, coming in packs to try and overwhelm your Squad.
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Alien Prowler
Prowlers seem to be based on the Alien Sentries described by the Alien RPG, being the Warrior version of a Runner.
Prowler's design seems to take inspiration from classic Kenner toys, the Cougar Alien come to mind, aside from that, it's a Red runner with sharper shoulders, neck spikes and a crowned head.
In gameplay, Prowlers will act in 2 manners, ambushing and rushing. Ambushing is self explanatory, the Prowler will wait in a corner, wall, ceiling or even behind objects to try and pounce on unaware Marines. Prowlers will rush at the players when they spawn alongside packs of Runners, usually rushing at the Fireteam in pairs.
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Alien Burster
Bursters seem to be mutated Runners that scream in pain while rushing at the Fireteam, Colonel Shipp entertains the thought that they are born from local wildlife.
In gameplay, Bursters act exactly like Runners, being a bit more tanky, noisy, and exploding into dangerous pools of acid upon death.
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Alien Spitter
Spitters seem to be mutated Xenomorphs, showing signs of decay and looking completely unnatural. As suggested by the shape of their heads and in-game dialogue, Spitters seem to have been affected by black goo at some point before maturing, resulting in this intriguing creature.
Design wise, Spitters resemble a hybrid of a Neomorph and a Xenomorph, with sacks of glowing acid growing out of their decaying skin.
In game, Spitters will keep their distance for the most part, spitting balls of acid at the Fireteam, if the ball doesn't hit a player, it will form a puddle of acid on the ground.
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Alien Drone
The Drone is the basic human spawned Xenomorph. Being a semi rare and dangerous spawn.
The Drone is the classic and titular Alien, his design being inspired by good old Big Chap, but with some clear liberties taken for style.
In game, the Drone can mow down an unprepared Fireteam's HP, and sometimes, come back to do it again! The Drone works in a similar style to it's Isolation Counterpart, he will spot you, he will rush at you, he will beat your ass, then hide in the vents to come back and do it all over again, the Drone can be scared off if enough damage is applied.
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Alien Warrior
A show stealer, the Warrior will make it's presence known the moment it enters into battle, another human spawned Xenomorph.
The Warrior is based on it's counterpart of the same name from the second movie, it has the same liberties added to the Drone applied to it.
In gameplay, the Warrior is a tank that is quick on it's toes to get on your face and try to rip it out. Aside from armor and a big health pool, the Warrior can also grab onto a Marine to try and impale them with it's tail.
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Alien Praetorian
Royal Guards to the Queen and evolved adult Drones, Praetorians are mean, fast and dangerous.
Possibly the most unique take on a Praetorian yet, having a white exoskeleton instead of the average dark or pale colors of other iterations, and the first time a Praetorian appears in a solo Alien game!
In game, Praetorians work as mini bosses that function similarly to the Warrior, but faster, stronger and bigger. With all new animations and sounds too.
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Alien Crusher
The Praetorian counterpart to the Runners, Crushers are fast moving tanks.
Same deal as the Praetorian really
In game, Crushers have bullet proof heads and sometimes come in pairs, it functions like a tank.
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Ovomorph and Facehugger
Every Xeno has to start somewhere.
Design is pretty standard, but the models do look good.
Facehuggers seem a bit like jokes if you take care of the eggs first, that is until you walk past an egg you didn't see, and that hugger comes back to pounce on your face while your Team is dealing with Prowlers and Warriors. Due to their small size, Facehuggers are hard to see in the middle of battle, and can be a dangerous nuisance that can lead to the failure of a mission, but can also be completely avoided by smart Marines.
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Alien Queen
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Variations
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Elite Drone - Mini-Boss Variant of Drone Has a Scripted encounter on E1M2, named as Monica, may appear as a future common enemy.
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Radioactive Spitter - Mini-Boss Variant of Spitter Rare spawn on Horde mode, slim chance of showing up on campaign missions.
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