Metroids are the titular creatures of the Metroid series. They are organisms created by the Chozo. First discovered on the planet SR388 years after their introduction, they were promptly used as a bioweapon by the Space Pirates. Metroids feed on the "life energy" of their prey in a manner similar to the way a leech drains a host organism's blood. Unlike leeches, Metroids leave all of their prey's blood and internal organs intact yet lacking the energy necessary to sustain life.
Powers and Stats
Tier: Unknown | At least 6-C | 5-B | At least 5-B
Name: Metroid, Ultimate Warrior (Chozo Translation of Metroid)
Gender: Hermaphrodite (the Queen Metroid doesn't need a mate)
Age: Varies (A Metroid will change forms as it grows older, Omega Metroids being considered full adults.)
Classification: Alien parasite, Galactic apex predator
Powers and Abilities: Superhuman Physical Characteristics, Superhuman Speed, Levitation, Life Absorption, Transmutation (Turns the host's body into dust when touched.) Size Manipulation (Grows larger with the more Energy it absorbs.) Transformation. | All previous abilities, Electric Armor as an Alpha Metroid, Energy Projection as a Gamma Metroid, Can electrify the battlefield, Fire Manipulation. | All previous abilities, Regeneration (Mid-Low) as an Omega Metroid, Metroid Hatchling Summoning as a Queen, Acid Manipulation as a Queen, Invulnerability.
Attack Potency: Unknown (The Galactic Federation stated that a single metroid has the potential to wipe out a whole army, attacks depend on life-draining abilities) | At least Island level (Capable of damaging a basic Post-Zero Mission Power Suit) | Planet level (Capable of taking on Varia Suit Samus) | Unknown (Drained the life from Gravity Suit Samus) | At least Planet level (One-shotted a weakened SA-X after it fought Samus, is capable of reducing Fusion Gravity Suit Samus' health from 20 full Energy Tanks to 1 health remaining in one claw swipe).
Speed: Massively Hypersonic+ (Capable of reacting and damaging the Pre-Zero Mission Varia Suit Samus) | Massively Hypersonic+ (Capable of reacting to Post-Zero Mission Power Suit Samus) | Massively FTL+ (Capable of reacting Post-Zero Mission Varia Suit Samus for the Omega Metroid and Metroid Queen, for the Baby she is capable of reacting to Gravity Suit Samus, and as the GF Omega Metroid, she is capable of tagging SA-X and Fusion Gravity Suit)
Lifting Strength: Unknown
Striking Strength: Unknown | At least Island Class (Strikes Post-Zero Mission Varia Suit Samus as the main form of attack) | Planet Class (Capable of inflicting severe harm to Post-Zero Mission Samus) | Unknown (As the Baby she was not capable of inflicting damage through conventional means, like its larval stage) | At least Planet Class (Casually swiped away the entirety of a weakened SA-X's health, reduced Gravity Suit Samus from full health to 1 health in one claw swipe)
Durability: Planet level (Resists all of Samus' normal weapons unless frozen), Island level when frozen. | At least Island level (Can take hits from Legendary basic power suit Samus). | Planet level (Able to resist attacks as the Omega Metroid and Queen Metroid, Able to attack Mother Brain as the Baby.) | At least Planet level (Resisted several of SA-X/ Fusion Gravity Suit Samus' hits)
Stamina: Varies depending on how much energy they have consumed, but it is incredibly high, on average
Range: Standard Melee Range | A couple of Meters as a Gamma Metroid, and about the size of a room by electrifying the floor. | Extended melee as the Baby and a few meters as the Queen Metroid.
Standard Equipment: None notable
Intelligence: Basic animal instincts, however, as an Omega Metroid it shows signs of being able to use strategy, including attacking in more than one ways at once to surprise attack the enemy.
Weaknesses: Weak to extremely cold temperatures, Younger ones can be frozen alive at 0 degrees Celsius, Metroids retain this weakness to cold for their entire life cycle, but older Metroids become far more resistant to it.
Key: Standard/Larva Metroid | Alpha, Gamma, Zeta Metroids | Omega Metroid, Queen Metroid | The Baby/Super Metroid | GF Omega Metroid
(Credit to Metroid-Database for most of the images.)