Zeelas are quite agile and can climb walls and hang onto ceilings with little difficulty. They are native to Brinstar and Kraid's Lair on Zebes. Like the near-identical Geemers of Crateria and Norfair, Zeelas seem to be nothing more than indigenous lifeforms and not a biological weapon used by the Space Pirates. According to the Metroid manual, they have no bones.
They come in three known variations: Green, Yellow, and Red. They are all identical in behavior to Zoomers, Sovas, and Geemers. In Metroid: Zero Mission, the red version's eyes will fall off when the creature is destroyed, damaging Samus if they come into contact with her.
Zeelas were captured and brought aboard the Biologic Space Laboratories research station prior to the events of Fusion, where they were eventually infected and mimicked by the X Parasites. Through the X's ability to manipulate their victims' DNA, these Zeelas could now inhabit the sub-zero temperatures of Sector 5, unlike their original forms that lived in the tropical areas of Zebes. X-infected Zeelas were more grotesque in appearance than their unmodified counterparts; they also gained tube-like protrusions on their sides which they used to fire tiny sparks of energy in arcs.
"These boneless animals creep along horizontal and vertical surfaces. They normally live underground. The blue ones are the strongest."
"Crawls around the floor and ceiling, moving its eyeballs."
"This enemy moves like Zoomers and lives underground. His defensive power is stronger than Zoomers’."
|Color||HP||ATK||E||BE||M||SM||PB||Brinstar. Moving slowly on lush surfaces, they only serve to get in your way.|
"Kreela's slow and quite easy to destroy, taking just a couple of hits."
- In the Captain N: The Game Master episode "Game Boy", which prominently features many enemies from Metroid, Simon is attacked by a pair of hopping creatures while exploring Metroid. While they are not referred to by name, certain aspects of their design (particularly the large eyes, arthropod features, and blue/orange color scheme) suggest that they may be Zeelas.
- Metroid Prime and Metroid Fusion: Prima's Official Strategy Guide erroneously refers to Zeelas as Bulls, despite otherwise correctly identifying the latter species.