Zeta Metroid

The Zeta Metroid is the sixth natural stage of a Metroid's life cycle. They appear as enemies in Metroid II: Return of Samus and its remake Metroid: Samus Returns. They also have a minor appearance in the Restricted Lab of Metroid Fusion.

The Zeta Metroid possesses a very different structure from all prior forms, as it now resembles a reptilian dinosaur. This stage is the beginning of the species' adult phase, and thus requires a lot of firepower to kill. However a weak point can be exploited by shooting the Zeta Metroid in the dorsal region which multiplies the damage it receives. The Omega Metroid is the next and final stage for all standard Metroids.

Samus Aran encountered three Zeta Metroids during her mission on SR388.

Physiology
After an undetermined period of time, a Gamma Metroid's backside splits open and the Zeta Metroid sheds the body like a butterfly sprouting from its chrysalis. The organism now possesses two arms and two legs with claws on each end, allowing it to stand in a bipedal position with a tail on its rear similar to an arthropod. Three blue compound eyes are present on each side of the head which is now separated from the rest of the body by a short neck. It now has a leech-like mouth and can spit hazardous substances. The creature is smaller than a Gamma Metroid, giving it quite a bit of maneuverability as it flies in the air. The membrane which houses its nucleus is located on its torso.

The Zeta Metroid's design is changed considerably in the remake Metroid: Samus Returns. The creature is far more slender and massive in height, with its arms, legs, and tail being much longer in length than Metroid II 's design. The Zeta is mostly seen in a quadruped stance and possibly can no longer fly. The head has been given an additional pair of eyes, making for a total of eight compound eyes instead of the original's six; they are now of a red color as well. Finally, the head of the Zeta Metroid is greatly elongated, reaching all the way to the middle of its back when the creature is on all fours.

Behavior
In Metroid II: Return of Samus, the Zeta Metroid perpetually floats in the air, occasionally making quick dives toward Samus and then coming to a halt in order to spit large globs of damaging fluid. It is during this sudden stop that Samus can easily shoot Missiles at the Metroid's front. If she is skilled enough to outmaneuver the Zeta Metroid and get behind it, she can shoot at its back which multiplies the damage of each Missile nearly twofold.

Metroid: Samus Returns has a drastically different battle sequence for Zeta Metroids. Instead of flying, they crawl along the ground as well as climb on the walls and ceiling. As they do so, they will attack with either a medium ranged flamethrower from their mouths, or shoot long ranged green spheres of burning plasma-like energy. Occasionally, a Zeta will charge up the latter projectile while on the ceiling and launch a barrage of six; these charged projectiles will continuously bounce off of the room's surfaces and will not dissipate even if they hit Samus. It is at this specific moment that Samus can use her Grapple Beam in a similar fashion to the Grapple Lasso, grabbing onto the Zeta Metroid's back and smashing it against the floor. The creatures can also lunge at her as a melee attack which she can parry with her Counter, however Zeta Metroids can catch her off-guard by immediately counteracting and leaping on top of her, giving Samus yet another opportunity to parry them.

Manual
"Multiple mutations will cause a Metroid to continue to grow into an even larger and more powerful adversary."

Nintendo Power issue 31
"The fire-breathing Zeta Metroids are equipped with armor on their lower bodies. You'll only hurt them from the side."

Trivia

 * The Zeta Metroid have a resemblance to the titular Aliens from the film series of the same name, and is perhaps another reference to the franchise. This similarity is further highlighted in Metroid: Samus Returns with its redesign (in particular its elongated head and its ability to climb on any surface), as well as the Zeta Metroid's debut where it drools over Samus, lowers its tail before dropping down and slowly lifting its head; this is a clear homage to the first appearance of a full grown Xenomorph in the movie Alien.

Gallery
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