Fusion Suit Samus is the alternate suit she gained first in Metroid Fusion; it has since appeared in many fan games.
Samus' Fusion variant appears in Smash Theta, replacing the usual mainstay Power Suit variation.
- Blue: Basic; From Metroid Fusion.
- Red: Resembles the Phazon Suit from Prime 1.
- Purple: Inspired by the Gravity Suit from Fusion
- Yellow: Varia Suit from Fusion.
- Orange: Power Suit from Fusion.
- Green: Inspiration Unknown.
- White: Resembles the silver-and-white Light Suit from Prime 2.
- B: Beam Shot. Fires a fully upgraded beam similar to Other M's beam.
- Side B: Ice Missile. Shoots a chargeable missile that leaves a freezing effect in wake of its explosion.
- Up B: Shinespark. Rushes upward, similar to Fire Wolf.
- Down B: Power Bomb. Unleashes a powerful explosion, damaging all foes in range. Needs to recharge over time.
- Final Smash: Hyper Beam. Similar to Zero Laser, except Samus doesn't transform into Zero Suit Samus.