Proving Grounds is a room in the Pirate Research sector of the Pirate Homeworld in Metroid Prime 3: Corruption. The room is large and circular, and contains a lift to link between floors of the facility.


This area is where Samus fights Gandrayda in Metroid Prime 3: Corruption. There is a lift in the center of the room that can be deactivated if intruders are needed to be contained. Several large shutters border the edges of the room, and can be opened to expose the rim of the area to the planet's sky.

The lift can be activated by entering a hologram. The lift and the exit door of the room can be disengaged by use of a control terminal. Samus can restore power to the lift and remove the shield covering the door by using the Grapple Voltage, which she acquires after defeating Gandrayda.

The name of the room may indicate that it is used as a battle arena by Pirates, or refers to Gandrayda's desire to prove herself to the Pirates by killing Samus and presenting her "bloody helmet" to Dark Samus (according to Space Pirate Data).

Battle with Gandrayda[]

You know, you should never trust strangers, Sammy. This is going to be fun.


The corrupted Gandrayda reveals herself to Samus

Samus enters the room below this one, the Proving Grounds Lift. She meets up with who is believed to be Federation Trooper NZG41, and together they reactivate the lift and use it. After reaching the top, Samus walks towards the door in the Proving Grounds, but becomes uneasy when she does not hear the Trooper following her. Sensing danger, Samus suddenly enters Morph Ball mode. The Trooper fires at Samus, but she manages to dodge it, and returns aim at the Trooper. NZG41 then reveals "himself" to be Gandrayda, and the two Bounty Hunters begin battle.

When the battle starts, Gandrayda will jump, flip and run about the room, making it hard to shoot her. She can throw blades that will lock onto and "seek" Samus, though they can be shot down for Energy Capsules and Missile Ammo. Gandrayda will also use a ground-based impact wave that streaks directly towards Samus.

At 75% health, Gandrayda opens the shutters, covering a portion of the battlefield in deadly Acid Rain and raises pistons from the floor. She will then continue her attack, and will also begin using new transformations.

Once defeated, Gandrayda screams in agony as she rapidly cycles through different forms (Aerotrooper-G, Rundas-G, Swarmbot-G, Ghor-G, Berserker-G and finally Samus-G). Unable to save Gandrayda, Samus looks away with a clenched fist as a Dark Samus specter arrives and absorbs her.

After the battle[]

Gandrayda leaves the Grapple Voltage for Samus.

Afterwards, Samus can drain the energy from the Grapple Voltage Terminal to escape, and board a Transit system tram back to her Gunship. The Proving Grounds can be returned to at any time, and it is useful to pass through here after Samus acquires the Spider Ball, so she can almost instantly get to the Craneyard where the Hazard Shield is being held. A Red Phaazoid can be found here after the Pirate Homeworld Seed is destroyed.

Connecting rooms[]



Grapple Voltage
"Grapple Voltage"
Grapple Voltage Terminal
"Terminal provides power to energy shield. Drain the device of power to remove the shield."
Grapple Voltage Terminal (drained)
"Terminal is drained of power. Nearby energy shield is offline. Able to access transit station."


"The Grapple Voltage ability is used to give or take energy from certain objects.
Grapple the power coupling by locking on with Wii Z button.png and cast the Nunchuk forward.
While still attached, pull the Control Stick down Wii stick down.png to siphon energy from the coupling."