The Spider Guardian was a Darkling Pillbug possessed by the Ing that stole Samus's Spider Ball, which Samus Aran retrieved by defeating it in the Dynamo Works of the Sanctuary Fortress.


Boss spiderguardian3

The first phase of battle with the Spider Guardian.

The Spider Guardian does not actively attack Samus, and instead moves along an extensive, labyrinthine Spider Ball Track while shielding itself with a damaging magnetic field. Morph Ball Bombs merely weaken its shield, and it can only be damaged by forcing it to collide with Electric Coils. To do this, Samus must weaken the Spider Guardian's shield until it turns green, and then the Guardian will move slower. Samus must quickly reach and then activate the Bomb Slots in the room in the correct order so that the Guardian's course is altered enough to drive it straight into an Electric Coil. This progressively gets harder and harder until the last Coil is destroyed, and the Spider Guardian dies.

Logbook entryEdit

Spider Guardian

Metroid Prime 2: Echoes

Temporary scan

Morphology: Spider Guardian
Spider Ball powered darkling. Target uses Spider Ball power to cling to walls. It seems to have a connection to the energy system in the area. Overexposure to energy may disrupt it.

Logbook entry

This darkling Pillbug has absorbed the power of the Spider Ball. It can travel over magnetically charged surfaces at will. The creature seems to have a connection to the local energy system. Aggravating it may cause disruptions to the system.


  • The Spider Guardian boss battle is infamous for its high difficulty level, generally considered to be one of the most difficult bosses in the game. Multiple reasons for this exist: the large distance from the Save Station, the great amount of damage the charged "aura" can deal to Samus upon contact, a limited amount of energy recharging, the sometimes unpredictable patterns the boss moves in the last phase (with a tendency to get in the way), and the need to do precise Bomb Jumps within a very tight time limit in the last part of the fight. The fight's difficulty was heavily toned down in Wii versions of the game, partially due to the addition of the Spring Ball, and the boss doing less damage than it did in the GameCube version.
  • The Spider Guardian is the smallest boss in the Metroid series.
  • The Spider Guardian and Bomb Guardian are the only Sub-Guardians to not be fought on Dark Aether.
  • The Spider Guardian is one of only two bosses in the Metroid series that is "fought" in Morph Ball mode alone, the other being the Caretaker Class Drone. Both are from Echoes.
  • The Spider Guardian can only be scanned prior to the battle, since Samus cannot come out of the Morph Ball mode once the battle begins. She can scan it while it runs along a Spider Ball Track through a window or by the hole in the room prior to the fight.
  • If Samus attempts to exit the fight with the Spider Guardian by going through the hole where she entered the battle, and opens the door, the game will crash.[1]
  • The Phazon Pillbug, a corrupted Pillbug from Metroid Prime 3: Corruption, resembles the Spider Guardian.
  • In the demo, the Spider Guardian was called Spiderling.
  • If Samus uses a Power Bomb on the Spider Guardian via Sequence Breaking, it will be instantly vaporized. However, it does not release the Spider Ball or destroy the electrical conduits, thereby trapping Samus in the room unless the battle is restarted.[2]
  • If the first bomb slot in the last stage of the Spider Guardian battle is activated at a precise point in the boss' movements, it will cause the Spider Guardian to collide with what is usually the "second" coil to be destroyed. Despite this, the camera will still zoom in on the first electrical coil during the cutscene while the guardian is taking damage. When the Spider Guardian later hits the "first" coil, the camera will zoom in on the empty space where the second coil was.