The Power Bomb Guardian is a boss in Metroid Prime 2: Echoes. It is a Sporb possessed by the Ing that took Samus's Power Bombs at the beginning of the game. Defeating it subsequently gets Samus her Power Bombs back.
Battle[]
The Power Bomb Guardian is fought in the Undertemple in the Dark Torvus Bog, residing on a column in the center of the room. It is immune to Samus's weapons; the only way to kill it is by crushing it with a bridge directly above it. The bridge is held in place by four Bomb Slots. Samus must use the Spider Ball tracks that circle the room to get to the slots while avoiding the Power Bombs that the creature throws at her.
The Power Bomb Guardian is somehow able to anticipate Samus's movements and targets spots in front of her. As it takes more damage, the beast throws multiple Power Bombs at Samus. After activating all four Bomb Slots, the Power Bomb Guardian is squashed by the bridge, and a new track appears, allowing Samus to get to the bridge and reclaim her Power Bombs.