Explosion Expander is a Normal Item from Wario Blast: Featuring Bomberman! that increases the explosion range of placed bombs. After collecting this item, the explosion range of one's bombs increases by one tile, collecting more Explosion Expanders increases the range further (up to four). The item can be picked up and used by players and opponents.
In Round 8, the player and the opponents have four Explosion Expanders equipped from the start of each level.
One of the effects of the Skull prevents Explosion Expanders from working.