The Aqua Alien reflects the typical biomechanical features of a standard Xenomorph. Like some Warriors, it is bluish in color, but like the Runner, has some reds to its body. The front of its chest and top of its dome it splattered and striped red, respectively. The head also has a fin, not unlike a sailfish, as well as two protrusions. Its legs are digitigrade in shape and have fins. The creature's fingers and toes appear to be webbed.
The maw of the creature is enlongated, with longer teeth. Its tail also resembles a shark or whale with a Xenomorph spin.
- There is another more overtly aquatic alien: the Swimming Alien.
- The red stripe dorsal down it's dome resembles the Cystic mark on Warriors, Drones, and Predaliens when their hosts are infused with Cystic Acid prior to being infected by a Facehugger.
- According to the Box of the figure, Aqua Aliens are genetically enhanced Xenomorphs.