Regulus

Regulus is one of Altair's mercenaries from the video game, Bomberman 64, and perhaps the most significant of the three, even more so than Altair himself.

Though initially a villain, Regulus eventually turns good.

Bomberman 64
Regulus is symbolized by the color blue, despite his level being White Glacier. He attacks by planting bombs and charging at his enemy.

Bomberman fought Regulus on Stage 2 of White Glacier. He defeated him, and Regulus left, saying Bomberman has upset him.

Later, after Bomberman defeated Altair at Black Fortress, Regulus showed up to save him, but Sirius attacked them both at once, knocking Regulus over the edge.

During Bomberman's fight with Sirius on Rainbow Palace, it is revealed that Regulus survived, and just as Sirius was about to kill Bomberman, Regulus knocked him out of the way and slashed the Omni Cube a few times, destroying it. Bomberman and Regulus then fought Sirius together, and destroyed him.

As Rainbow Palace collapsed on top of Black Fortress, destroying them both, Regulus saved Bomberman from the explosion. He tells him he respects him, but still dislikes him, and promises a rematch, and flies off.

During the credits of the true ending, outtakes are shown of the battles with the four minibosses. In Regulus's case, as he is swinging his claws in a slashing motion on top of the stalagmite, he loses his balance and falls off.

Bomberman 64: The Second Attack
Sometime after the fight with Sirius, Regulus became one of the seven Elemental Knights, the knight of Shadow. It was he who possessed the Shadow Stone. Then, the Elemental Knights were brainwashed by Rukifellth (who in turn was possessed by Sthertoth), and became the Astral Knights. Regulus was only pretending to be under Rukifellth's control; nevertheless, it did have some effect on him, and unlike the others, his name changed to Bulzeeb.

Upon hearing the description of Bomberman after Baelfael, the Elemental Knight of fire, was defeated, Bulzeeb immediately knew who he was, though he denied it to anyone else. Bomberman fought Bulzeeb on Prison Planet Thantos. His attacks shown here are:
 * Nightmare, where he charges at the enemy for 2 damage
 * Summon Horror, where he shoots a dark bird of shadow for 2 damage
 * Gravity Sphere, where he creates a black hole to follow his enemy. If it sucks him in, it's instant knockout.
 * Dark Illusion, an Instant Knockout dash attack where he punches and kicks the enemy and then sucks them into a black sphere

Bomberman defeated Bulzeeb, and then the goddess Mihaele appeared and tried to make Bulzeeb remember that he is the Elemental Knight Regulus, not the Astral Knight Bulzeeb. Bulzeeb was not interested, and gave Bomberman his Shadow Stone and left.

When Bomberman defeated Zoniha, the Elemental/Astral Knight of light, she attempted to destroy him with a massive orb of light, but Regulus used a Gravity Sphere to suck it into oblivion. He then killed Zoniha with another Gravity Sphere.

On Warship Noah, Bulzeeb fought Rukifellth but was defeated. When Bomberman arrived, Bulzeeb/Regulus gave him all his remaining strength, healing any injuries and powering him up to the maximum. Rukifellth then killed Regulus with a powerful Gravity Sphere.

After the Angel of Light and Shadow was defeated, Regulus was brought back to life as an Elemental Knight, along with the others. He leaves to begin training again, saying that he will have his rematch with Bomberman some other time. He has not been seen since.

In an alternate ending, if a player does not collect both the Shadow and Light Stones, or else if a player is killed by Mihaele's Bludgeoning Blow, and then defeats Sthertoth: God of Chaos (as opposed to the angel), Regulus is not revived, and remains dead. Regardless of whether or not he is fought on Thantos, his confrontation with Rukifellth remains the same.

Quotes
"The four of us were barely able to steal the Omni Cube from him. Yet you were able to defeat him. I must respect your abilities, but that doesn't change the fact that I dislike you! Someday you and I will settle this. Until then, take care of yourself. (after Sirius, Rainbow Palace, and Black Fortress are destroyed)
 * "Not bad. I underestimated you. However, you've upset me. Prepare to meet your fate." (after being defeated by Bomberman)

Trivia

 * Regulus is similar to the Dragonball Z character Vegeta, seeing as they both lost a battle to the main character and want a rematch. Also both are brainwashed by an evil villain, but are not fully under his control, and are eventually killed trying to fight them, and are later brought back to life.