Spider Ball

The Spider Ball is a special power-up for the Morph Ball, featured in Metroid II, Metroid Prime, Metroid Prime 2: Echoes, and Metroid Prime 3: Corruption.

In Metroid II: Return of Samus, the Spider Ball is one of the most important upgrades to exploration. It allows Samus to cling to walls and ceilings when in Morph Ball form, thus allowing her to reach nearly anywhere in the game.

The Spider Ball is acquired in Metroid Prime and Metroid Prime 2: Echoes by defeating a boss, and in a hidden room in Elysia in Metroid Prime 3: Corruption. The spider ball lets Samus ride along magnetic rails that are dotted around the areas she goes around called Spider Ball Tracks. If she uses a Morph Ball Bomb, the Morph Ball will make a vertical hop like on regular ground. If she uses the Boost Ball (only in the later two Prime games), she will leap in the opposite direction from the track, often with enough power to shatter thick glass.

This is usually used to get to hidden areas with a Missile Expansion or Energy Tank. When ever Samus encounters a magnetic rail in the morph ball, she can use the Spider Ball, as well as the Boost Ball and Morph Ball Bombs to reach new areas unreachable before, or to even defeat bosses. And to get to some of those areas or beat those bosses, complex Spider Ball puzzles are in Samus' path. Such courses require Bomb Jumps, Boost Ball leaps, and even timed releases and re-attachments to tracks. On two occasions Samus have to beat a boss to proceed: against the Power Bomb Guardian, and the Caretaker Class Drone. Both require careful maneuvering in order to succeed.