Samus Aran

"Samus made her first appearance in Metroid (1986) for the Nintendo Entertainment System. The original game concepts for Metroid were done by director Makoto Kanoh and designer Hiroji Kiyotake.

In almost all of her missions, Samus is equipped with an armored "Power Suit" created from Chozo technology. The Power Suit, through its numerous upgrades, protects Samus from hostile environments and allows her to use a wide variety of high-powered weapons such as beams, missiles and bombs. In some games, such as the Metroid Prime series, Samus' Power Suit also allows her to scan environments and enemies for additional information. Throughout the series, Samus executes missions given to her by the Galactic Federation, typically to thwart the plans of the nefarious Space Pirates and their leader, Ridley.

The original Metroid kept Samus' gender a secret (with the intent of surprising gamers after they completed it); even the game's instruction manual refers to Samus as a male. However, clearing the game would unlock an ending where Samus would remove her Power Suit to reveal a bikini, and the well-known "JUSTIN BAILEY" cheat code would allow her to be playable in a leotard. Since then, almost every game in the series would depict an unsuited Samus in some way, typically as part of an ending sequence. Metroid: Zero Mission and later games would consolidate Samus' appearance and abilities outside of the suit, resulting in the version of the character known as Zero Suit Samus.

Much like Link, Samus is largely silent during gameplay and defined by the player's actions, although she is occasionally given spoken dialogue or internal/introductory monologues, with her level of expressiveness varying between games. This carries over to both her incarnations in Super Smash Bros., where the "standard" Samus is completely silent (although the Galactic Avenger event description in SSB4 is written as if spoken by her) and her Zero Suited self has a small number of spoken lines. Metroid: Other M attempted to introduce more personality, characterization and backstory to Samus; however, after the game's approach resulted in significant fan and critical controversy, Metroid Prime: Federation and, more prominently, Metroid: Samus Returns, in addition to subsequent Super Smash Bros. games (particularly through small amounts of characterization such as in Ridley's reveal trailer), would revert Samus to her previous, largely silent depiction."

Samus may also enter battle in her Zero Suit

"While Samus has been shown without her Power Suit since the original Metroid, usually as part of an ending sequence, the Zero Suit first appeared in Metroid: Zero Mission, a remake of the original Metroid for Game Boy Advance. The original Metroid allowed Samus to be playable in a leotard using the well-known "JUSTIN BAILEY" cheat code; Zero Mission expanded on this by incorporating a playable, suitless Samus into the game's narrative for the first time, granting her a unique style of stealth-based gameplay. Ever since Zero Mission, Samus has appeared in her Zero Suit in every Metroid game except Metroid Prime Pinball and Metroid Prime: Federation , although the latter features a Zero Suit-inspired paint job for the playable Federation mechs unlocked via amiibo.

The Zero Suit covers Samus completely from neck-to-toe in a cyan, skin-tight bodysuit with magenta Chozo sigils on her back, left breast, and the back of her hands. While wearing it, Samus wears her hair in a ponytail, although she is occasionally seen with different hairstyles in different outfits (prior to the Zero Suit's debut, Samus would be more often seen with her hair loose). Although Samus' eye and hair color varied widely across early games, most current depictions consistently give her blonde hair and blue to turquoise eyes. Despite this, Samus' "Zero Suit" character design has varied in nearly every appearance. Initial appearances would depict Samus with a high ponytail with a red hair tie, long sidetails, and lean musculature. Metroid Prime Hunters featured a heavy redesign for the Zero Suit that was not used in subsequent games, with a more simplistic, gloveless bodysuit and a different hairstyle for Samus. Metroid: Other M featured another drastic redesign by changing Samus' eye color (now a more greenish hue), her general hairstyle (a lower ponytail and much smaller sidetails), her general build (now short and slim as opposed to lean and muscular), and the Zero Suit itself (which now has a more segmented appearance and is equipped with wedged heels). This general design was carried over to Metroid: Samus Returns, but with a few minor changes, most notably by giving Samus a blue hair tie and a more athletic body type akin to her Super Metroid appearance; an unused design for the game depicts her with an altered Zero Suit pattern, but she retains her Other M paneling in-game.

Within Metroid canon, Samus boasts superhuman athleticism even without her Power Suit, thanks to the Chozo infusing their DNA within her and training her in combat during her childhood. While she is also much more adaptive to alien environments than a normal human thanks to her Chozo DNA, she is still extremely without her Power Suit, and thus must rely on stealth and her Paralyzer instead of direct combat to achieve her objectives. However, much like her fellow bounty hunter Captain Falcon, Zero Suit Samus is depicted in the Super Smash Bros. series with a varied and highly physical martial arts fighting style that compliments her superhuman athleticism. She is also notable for her impressive flexibility and gymnastic skills, with many of her attacks involving her in splits, doing cartwheels, and more. In addition, her Paralyzer is equipped with Super Smash Bros.-specific design elements that grant it offensive potential. Ridley's reveal trailer in Super Smash Bros. Ultimate goes as far as to depict the Zero Suit as an alternate combat mode that Samus willingly uses against Ridley, in contrast to its canonical depiction."

via SmashWiki