Phazon Suit
Phazon Suit is the final suit upgrade in Metroid Prime. It is acquired during the cutscene after Samus defeats Omega Pirate in Elite Quarters. It has two functions:
- Once acquired, Samus will no longer take damage from Phazon
- This does not apply to the red Phazon inside the Impact Crater
- Samus will be able to fire the Phazon Beam at Essence, the final boss
Because this item is required to defeat the final boss, it is considered mandatory for every category, including Low%. By extension, since Omega Pirate requires the X-Ray Visor to defeat, this means that X-Ray is also mandatory in order to get Phazon Suit.
Additionally, having Phazon Suit increases your damage reduction to 50%.
Effect on Percentage Counter
An interesting side effect of this item being obtained inside a cutscene is the effect this has on the percentage counter. Normally the game updates the percentage counter when Samus collects an item, but since Samus doesn't physically touch the Phazon Suit, the percentage counter never gets updated. Even if Samus has collected 99 of the items, the item percentage will remain at 98% until Samus gets her last item, where it will jump to 100%. This is the game's way of correcting for this inconsistency.