- Type: Steel/Ghost
- Species: Spinskull Fakemon
- Ability: Sturdy (Immune to one-hit kill moves and survives a fatal attack from full health with 1 HP)
- Hidden Ability: Levitate (immune to Ground-type moves)
- Height: 0'8"/0.2m
- Weight: 14lb/6.3kg
- Body Style: Head
- Gender Ratio: 1M/1F
- Physiology: Gyrium appears as a light grayish human skull. It is flattened slightly, and only its upper jaw is present. Its lighter gray teeth form a ring around its base. Its head is hollow and thick. Its eyes consist of three circular layers, which can rotate to look at objects. It has several circles on its head, topping with a lighter dark one. Its eyes glow yellow.
- Gender Differences: None
- Special Abilities: If they find a discarded body of a Rotosteo or Skelefuge, they can attach to it and resume its functions. Most Gyrium aren't powerful enough to control them, though.
- Behavior: They usually lie immobile, waiting for an object to pass. If it is large enough to prey on, it will roll and attempt to attach itself to the prey's head, draining some of its life-force. If attacked, it will try to roll away; if it cannot escape, it will spin at the foe.
- Habitat: Gyrium congregate in forests, or areas heavy in ghost activity.
- Fakedex Entry 1: They gather in areas where Ghost Pokemon frequently appear. They attempt to attach themselves to the heads of whatever creatures they can reach.
- Fakedex Entry 2: Normally immobile, it can spin to escape or attack potential foes. They are drawn to the discarded bodies of Rotosteo and Skelefuge, and can repower them if they are powerful enough.
- Fakedex Entry 3: It is a gastly sight to find a Pokemon with a Gyrium attached to its head, draining its life force.
- HP: 52
- Attack: 70
- Defense: 65
- Sp. Attack: 55
- Sp. Defense: 52
- Speed: 20
- Total: 314
EV Yield: 1 ATK