Dark Suit

The Dark Suit is the first suit upgrade Samus Aran receives in Metroid Prime 2: Echoes and so far appears only in that game. It was created by the Luminoth to better defend themselves against Dark Aether's atmosphere. Samus aquires the Dark Suit after defeating Dark Agon's energy guardians, the Amorbis.

The Dark Suit reduces the damage Samus takes by 20%, protects against Dark Vapor excreted by Ingclaws, and filters out roughly 80% of the corrosive effects of Dark Aether's atmosphere so that Samus only loses approximately 1 unit of energy per second (as opposed to 5 energy per second with the Varia Suit).

Appearance
Visually, the suit is arguably the first dramatic depature from Samus's traditional Suit appearance since the addition of the Varia's shoulderpads in Metroid II. Most noticeably it features darker, more muted colors than previous upgrades, and replaces the traditional spherical features on her shoulders with rounded wheel- or disc-like protrusions, and two pointed struts protrude from the back, but these seem to be meant to support the Gravity Boost once acquired. Upon acquisition of the Gravity Boost, the Dark Suit's bulk increases slightly at the rear of the torso. At this point the suit rather resembles a Luminoth, with a near-spherical torso, minimal neck showing, and various red orbs dotting the exterior. The visor's shape also changes, making it closer in appearance to Dark Samus's. It is also worth noting that these red orbs, prior to the aquistion of the Gravity Boost, are featured on her back in a triad closely resembling The Dark Amorbis' eyes.

In Super Smash Bros. Brawl
The Dark Suit is one of six alternate suits Samus can use in Super Smash Bros. Brawl. While it takes the shape of the Varia Suit, it retains all of the Dark Suit's colors, including the brown and grey overall color, orange visor, and red spots.

Trophy
"A Power Suit that reduces damage taken from the atmosphere of Dark Aether. It is obtained after defeating Amorbis in the Dark Torvus Temple [sic]. With its increased protection, it greatly widens the range of exploration available in the toxic atmosphere. This suit was developed by the Luminoth, the native race of Aether."

GCN Metroid Prime 2: Echoes

Sticker

 * Dark Suit Samus - Metroid Prime 2: Echoes [Throwing] Attack +16  (All)

Trivia

 * It is possible to avoid the Dark Suit altogether via sequence breaking, thus making the game harder and more challenging for the player as Dark Aether will damage the Varia suit quicker than the Dark Suit.
 * Strangely, with or without the Gravity Boost upgrade, Samus doesn't "sink" in Dark Aether's poisonous waters, even in areas that would otherwise be deep enough to for her to fully submerge herself when she's in possession of this suit. The reason for this is unknown.
 * The Super Smash Bros. Brawl trophy of the Dark Suit incorrectly states that the Dark Suit was obtained in the Dark Torvus Temple, when in reality, it was obtained in the Dark Agon Temple.