Bikini

From Wikitroid, the Metroid wiki

Bikini
Samus in her Bikini in Metroid Fusion.
Featured in	Metroid Metroid II: Return of Samus Super Metroid Metroid Fusion
Properties	nothing

Samus Aran has put on a generic bikini swimsuit for several of her appearances. The first appearance of a bikini was in Metroid. Samus wears a bikini only if the game is completed in the very shortest amount of time. (These time limits have varied from under one hour to under two hours to under three hours, depending on the game.) In the original Metroid, each ending sequence but two (the "worst" of them) was notable for revealing that Samus, underneath her Power Suit, is actually a woman. (Not only was her gender hidden by the suit, but in both the American manual and press releases Samus was referred to as male. This was not an issue in Japan, where Samus was described with gender-neutral pronouns.) However, for several games after, the bikini continued to appear as traditional fastest-completion ending sequence attire, even though it is well-established that Samus is female. The persistent appearances of the skimpy bikini are likely intended as ‘rewards’ for beating the games quickly as Samus is considered to be attractive (something that is stated in the manga).

The bikini is a usable suit in the original Metroid, accessible by the famous "JUSTIN BAILEY" password and variants.

Samus Aran's Suits
Power Suit | Varia Suit | Gravity Suit | Fusion Suit | UAM 1 Phazon Suit | Dark Suit | Light Suit | PED Suit | Hazard Shield Zero Suit | Bikini