Sidehopper

Sidehoppers (Side Hoppers in earlier media) are enemies in the Metroid series, appearing first in Metroid and subsequently in Super Metroid, Zero Mission, Metroid Fusion, Metroid: Other M and as cameos in Metroid Prime and Metroid Prime 2: Echoes.

Description
Sidehoppers are insectoid, bipedal creatures that bear a striking resemblance to Dessgeegas; the majority of Sidehoppers are weaker than their relatives from Norfair except for the rare, green variant found only in Tourian (vulnerable to nothing but Super Missiles). The common Sidehopper is as big as Samus and has a pair of powerful, piston-like legs enabling it to perform great leaps, and two enormous mandibles hanging directly beneath its head. Sidehoppers have the strange ability to repel gravity; they can not only cling to the ceiling, but also jump from it then "fall" upwards back onto it.

In their original incarnation in Metroid, Sidehoppers, like many enemies in the game, had two different forms: one pale orange with a green head, the other vermillion with a blue head. The vermillion ones were more resilient and powerful than their cousins. In Super Metroid, there were three variations of these creatures: Small Sidehoppers (most likely juveniles), Normal sized and an extremely powerful and armored variant called Blue Sidehoppers.

In the remake Zero Mission, another creature related to the Sidehopper was introduced, currently known as the X-45G. These creatures were stronger than both the Dessgeega and Sidehopper species in the game.

This wildlife was also seen in Metroid Fusion, but these were either infected Sidehoppers from the Biologic Space Laboratories research station or imitations by the X Parasites. DNA modifications gave them thrusters at the bottom of each leg and added resistance to attacks. Another noticeable addition is their vicious look.

Metroid manual
"These powerful enemies attack Samus while hopping. Be careful, the Side Hopper's strength is second only to the Mini-Boss. Destroy him with one missile blast."

1986 manga
"This tough new enemy hops and jumps when attacking."

Official Nintendo Player's Guide
"It attacks Samus with a double-jump movement pattern."

Super Metroid manual
"Sidehoppers pounce on intruders with powerful legs."

Super Metroid Nintendo Player's Guide
"Because they bounce unpredictably, it's best to either shoot quickly or avoid them."

Combat
In the original game, Sidehoppers were very dangerous, the most powerful enemies in the Brinstar region, particularly the brown variety and the ones that walk on the ceiling. It is best to dispose of a Sidehopper with a blast from Samus' Missile Launcher or Screw Attack if available; to avoid confrontations, freeze them with the Ice Beam and flee.

Sidehoppers remain dangerous opponents in all their subsequent appearances, thus maximum firepower is advised. In Metroid Fusion, all Sidehopper-X are more armored than their normal counterparts, making them immune to uncharged beams. Sidehoppers are found in Sector 3 instead of Sector 2 where one would expect to find them.

Trivia

 * It is possible that the green armored Sidehoppers are unnatural and possibly created from Space Pirate technology. The fact that they were only found in Tourian supports this theory.
 * In Metroid Prime, the Biohazard Containment room on the Space Pirate Frigate contains a roaring inhabitant and a shaking door. Scanning the unit reveals images of a very Sidehopper-like creature, though no name is provided. The fate of this creature after the Frigate crashed is unknown; the unit door remains closed and still, suggesting it either escaped or died in the crash.
 * The scan reads: "Specimen Solitary Holding 1. Phazon level >> Unknown. Status >> Xenotropic life-form unstable. Use caution."


 * In Metroid Prime 2: Echoes, there is an Multiplayer arena named "Sidehopper Station". Appropriately, it is also shaped like a Sidehopper.
 * It is interesting to note that while Sidehoppers are native to tropical areas, they are found in Sector 3, the desert/volcanic habitat on the BSL station. Additionally, Dessgeegas, who live in volcanic areas, are found instead in the tropical Sector 2 aboard the BSL station. The X parasites are known to modify the abilities and DNA of their victims, which might explain this change of natural habitats.