Bomb

From Wikitroid, the Metroid wiki

Bombs are the basic weapons for Samus Aran's Morph Ball. Bombs can break certain objects, and are essential to defeat many bosses such as Spider Guardian and Amorbis. Bombs can damage enemies within a certain range. If Samus deploys a Bomb below her, she'll make a small jump, called a Bomb Jump. Bombs can activate Bomb Slots. A more powerful Bomb called the Power Bomb is also available. In the Prime Trilogy as well as in Metroid Prime Hunters you can only use 3 bombs in a short amount of time.

Bombs have appeared in every Metroid game.

In the 2D Metroid games, bombs appear as actual metal bombs, which flash until detonation. It is also possible to lay several bombs instead of the three at a time as in the Prime games. During the Prime Trilogy, bombs appear as a blue energy ball when dropped. When they detonate, they are surrounded by blue light. In the first two Prime games, they are used to do bomb jumps to small tunnels and to damage enemies. In Corruption, they still serve the same purpose, but a small flick upwards of the Wii Remote activates a Morph Ball Jump to be used as a faster alternative.

Morph Ball
Morph ball | Bombs | Power Bombs Spring Ball | Boost Ball | Spider Ball Hyper Ball