The Subspace Bomb Factory (Part I)
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This stage has many secrets on all floors and only the true door does not have secrets. This stage consists of many levels, which can be reached with the lift. The exit is not on the top, and the player could be easily confused. During the level, doors will become locked and may sometimes pit players with an enemy, a switch or both. Some have hidden doors if a certain requirement is met, such as defeating an enemy.
The stage ends with Samus and Pikachu bursting into the bomb factory, where they find the Ancient Minister, along with an army of R.O.B.s and Subspace Bombs. They prepare to fight, but the Ancient Minister looks resentful and doesn't want to fight.
 Playable Characters