The Furnace (機関室, Engine Room, in Japan) is a trap that first appeared in Super Bomberman 2. It is a large, 3x3 tile space Hard Block with a door in the middle of its lower side. A trail of Oil runs out from the door of the Furnace, looping back to another side of the same Furnace or to the door of another one.
When a bomb is placed on the tile space directly in front of the Furnace's door, the bomb is quickly pulled into the door and immediately detonated, sending an explosion out of the door. Shortly afterward, the screen will turn red and all of the Oil that is connected to the Furnace will ignite and explode.
Once ignited, a Furnace will remain active for the duration of the stage, with the oil reigniting at almost 10-second intervals. An active Furnace can be identified by its open door and steam emission. Bombs placed in front of an active Furnace will not be pulled into it.
Furnaces can be activated in order to clear out enemies in the stage, but as they can also harm the player, caution must be taken. In some cases, it may be necessary to ignite a Furnace in order to progress through a stage.
In Super Bomberman 5, when the Oil is ignited, instead of the entire Oil trail exploding at once, a flame travels quickly along the path, and the oil trail now explodes at almost 15-second intervals. The speed at which bombs are pulled into a Furnace and then detonated is now delayed, as opposed to being almost instantaneous.
- Super Bomberman 2 U.S. manual, pg. 6
- Super Bomberman 2 Hudson Soft Guidebook, pg. 32