User blog comment:KillRoy231/My review of the Deadly Six/@comment-477304-20131021001503/@comment-26973802-20131025164641

They also didn't have to change Sirius in Bomberman 64 with levels he obviously goes to once.

Sirius is found in every action stage and either gives you helpful hints or tells about Altair or a made-up story of his past. For Stage 4 bosses (and the stage 2 boss of Altair's level) he gives you remote bombs, which you use to defeat the bosses, thus killing Draco, Leviathan, Orion, Mantis, and Cerberus. (going to previous levels are both so the player can get the gold cards, or incase the player wants to play the levels again). And the stage 2 boss of Green Garden is a sparring match with Sirius.

After you collect 100 gold cards and beat Altair, Sirius reveals himself as the true villain. From here, whenever you encounter him in a previous action stage, he says "It is useless to oppose me. Lie down quietly and meet your end." The Stage 2 fight with Sirius makes him a robot version and changes his lines instead of saying "Let's see how strong you've become". And for the boss battles that require remote bombs, Sirius does not appear, but the remote bombs are found in a bombable box.