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The remainder of this article contains lore created collaboratively by the Blaseball community.

Blazibaal is a malevolent immaterial entity, rumored to be the originator of Blaseball. It had been imprisoned in Hell for millennia, for crimes against the sun—crimes so terrible it was forbidden to speak of them even in Hell.

According to rumors, Blazibaal invented the splort to combat its boredom. Covertly reaching its tendrils out of Hell and towards earthly stadiums and fields, it influenced and pushed mortals into playing Ancient Blaseball. When the games started, it discovered that it could feed on their energy - and thousands of years later, soon after the conclusion of Season β1 of Internet League Blaseball, Blazibaal's power had grown enough for it to break out of Hell.

The Hellmouth Sunbeams believe that Hellmouth itself is a manifestation of the Sun's hatred towards Blazibaal. From time to time, whenever a Hellbeast comes crawling out of Hell to replace an incinerated player, fans whisper to each other about damned souls, commanded by Blazibaal to rise from the Dugout to suffer Blaseball for an eternity. Incineration, after all, is the only way out.

Blazibaal is the central figure of The Temple of Blaz.