The Water Bomb, as its name suggests, is a bomb filled with water. When it explodes, the bomb will release the water inside onto whatever is nearby. It's generally used to extinguish fires.
Bomberman Generation[]
It is acquired by merging the Fire Bomb with the Water Balloon at 1-2 (Lake Mensor). It is used mainly to extinguish fire spots. In the stages that features low body of water, only these bombs could be used.
In the anime[]
The Water Bomb makes an appearance in the Bomberman Jetters anime in episode 39 where White Bomber was trying to master the Water Bomb in an attempt to defeat Max. However, the Water Bomb proved useless, as Max uses Lightning Bombs, which Water does not work against Lightning.