The Bomberman universe was created by the Angel of Light and Shadow, who was somehow split into two halves: A goddess named Mihaele, and a demon called Sthertoth. Sthertoth brought darkness to the universe, but Mihaele gathered warriors to fight the darkness and seal Sthertoth away in the Celestial Stone. She then hid the stone on Planet Kaos to prevent anyone from finding it.

Unfortunately, two space pirates named Lilith and Rukifellth arrived and found the stone. When Rukifellth touched it, his body was taken over by Sthertoth. He brainwashed the seven Elemental Knights, Baelfael, Behemos, Ashtarth, Zhael, Molok, Zoniha, and Regulus (Bomberman's rival, and with the brainwashing, he is renamed Bulzeeb), and collected all the stones except the Fire Stone, which Bomberman had in his possession. Soon, Bomberman arrived and fought against Rukifellth's BHB Army, and defeated all the Astral Knights (the brainwashed Elemental Knights). Of the seven, Bulzeeb survived but was defeated by Rukifellth, and gave his power to Bomberman before Rukifellth killed him with a Gravity Sphere.

Bomberman faced Rukifellth and defeated him, but with all seven Elemental Stones brought to him, Rukifellth revealed his true plan: To let Bomberman collect the stones and bring them to him. Whether he beat the Astral Knights or lost to them, it didn't matter - either way he still got the stones. He uses them to transform into Sthertoth, Demon of the Dark. Sthertoth's appearance is a demon with claws, spikes on his shoulder, reddish brown skin, a white, slightly skull-like face, horns, and a mohawk. For all his power, Sthertoth isn't really that hard, although he does take a lot of hit points.

After Sthertoth was defeated, he tried to suck the universe into endless darkness, but Mihaele stopped him and trapped him in an orb of light, and then reunited with him, turning them back into the Angel of Light and Shadow. The angel wanted to destroy the entire universe and create it anew, but Bomberman fought him and defeated him. The angel decided that Bomberman could protect the universe and that it still had hope, and vanished, returning Lilith and Rukifellth to normal and bringing all the Elemental Knights back to life.

The Angel's gender is a subject of debate. It sounds like and is referred to by many fans as a male, but at one point, Regulus says, referring to the angel, "It looks like she brought all the Elemental Knights back to life." Also, the angel uses the pronouns "We" instead of "I".