Volcanos are a type of trap in some Bomberman games. Appearing in fire-based worlds, they are large, stationary volcanos, typically taking up a 3x3 tile section of the map. They lie dormant for some time, seeming to be a part of the scenery, until they reveal their eyes and emit several fireballs before returning to dormancy. The fireballs fly up out of the top of the screen, and then land in random positions on the map, as announced by flashing shadows that appear at their landing points. When a fireball hits the ground, it may destroy a Soft Block, detonate a bomb, or damage a player (they do not directly affect other game elements, such as Core Mechanisms or monsters).
The volcano itself is indestructable.
In Bomberman '94, the fireballs only stun the player on collision.
In Bomberman Max, the traditional volcano trap appears as well as a second type of volcano. This other volcano trap appears identical to the traditional type, but rather than emitting fireballs, it lets loose a steady stream of lava from its "mouth", which pours downward until it hits a wall or bomb.
1. Super Bomberman 3 Japanese manual, pg. 17