A Reo (リオ rio?) (spelled Rio in earlier media) is an enemy in Metroid, its remake, Super Metroid, and Metroid Fusion.



Reos in earlier appearances stay immobile until they see a threat, at which point they execute rapid, continuous swooping dive attacks with their talons. In later games, starting with Fusion, they fly back and forth until their target is in sight, to which they will dive towards. Reos can take much more damage than most other early-game enemies in the first Metroid.

In Metroid: Other M, they have a new coloring and a melee attack that involves latching onto Samus and can be found in the Biosphere of the BOTTLE SHIP, often emerging from Fly Pods that resemble a giant brown compound. However, these Reos are the weakest variant ever encountered in any Metroid game, as they can killed with a single shot from the Power Beam. An example of it can be seen here: [1]


Reo-X have a more gruesome physical appearance than their natural counterparts, due to the X Parasites altering their DNA; along with the color change, they are larger in size and have far larger claws (appearing to be almost armored).

Similar enemiesEdit

The Gerutas of Norfair and Holtz of Ridley's Lair act exactly the same as the Reo. The War Wasps of Metroid Prime are designed similarly to them, especially the Other M variants. Reo were displayed with the capability to wield small firearms in Deceít Du Jour.

Official dataEdit

Metroid manualEdit

"These are also pretty strong. They zoom down to attack Samus from the upper walls. The red ones are stronger than the yellow ones."

1986 mangaEdit

"Flies from the ceiling toward Samus. The red ones have strong attack power and the yellow ones are weak. Several shots with the normal beam or one Missile will defeat them."

Official Nintendo Player's GuideEdit

"He attacks Samus from the ceiling. His defensive power is high, and he is hard to kill with a normal beam."

Super Metroid manualEdit

"These creatures have sharp claws and can withstand several hits."

Super Metroid Nintendo Player's GuideEdit

Enemy Data Description
Color HP ATK E BE M SM PB Crateria/Brinstar. They fly in diagonal patterns and look like giant moths.
Normal 45 15 12 31 33 4 4


Super Metroid Players' GuideEdit

"Flying creatures that swoop in quickly to attack. A couple of hits is all that's required to deal wit them but you have to be swift as they're very fast."

Nintendo Official Guidebook for Metroid Other MEdit

Warning: Fan Translation(s) Ahead

This article, section, or file contains text that is unofficially translated by Wikitroid editors. Some information (such as proper English names of characters or items) may not be accurate. If an official translation becomes available, the fan translation(s) may be replaced.


"Rios are a series of bug-type flying creatures. In Sector 1 is the Rio, Sector 2 is the ice-attack wielding Himella, and Sector 3 is the fire-attack wielding Mella, making 3 different types of Rio."

The Japanese guide describes these as belonging to a Rio [sic] species, or リオ系 (Rio-kei?) (see image to the right).

Super Smash Bros. for Nintendo 3DS TrophyEdit


Super Smash Bros. for Nintendo 3DS Trophy.

"These clawed, fly-like enemies from Metroid show up in Smash Run, too. They float in midair, then fly in a U shape when you get close. They're predictable, which makes them easy to outsmart, but stay on your toes anyway—their attacks can send you flying. One way to beat them is to grab and throw them when they buzz near you. "

The PAL version of the trophy changes the spelling of "midair" to "mid-air".

Smash TipsEdit

"These enemies swoop down from above to tackle fighters. However, they can't actually hit you if you're directly below them. Give it a try!"


  • At the beginning of Metroid: Other M, Samus will encounter a Reo while running down a hall in the Main Sector. It will latch onto her and knock her down to the floor. This encounter is unavoidable.
  • Dragotix and Grippers are also sometimes seen feeding on Reos. This is similar to Gerutas in Zero Mission when ensnared by Tangle Vines.
  • The Japanese strategy guide for Metroid: Other M states that Mellas and Himellas are in the same species as Reos. It also spells, in English, Reo as Rio.
    • This may also mean that Mellows are related as well, although they are not featured in the game.
  • Metroid Fusion: The Official Nintendo Player's Guide refers to Reos as a "buglike beast".