The Architect is the creator of the BZPB multiverse, and the most powerful being to ever exist, capable of manipulating inter-universal non-space and crashing universes into each other as if they're toy cars.
He is also a shining, glorious example of a deus ex machina.
The Architect, better known as User:Heat, created the BZPB Multiverse. He and his fellow "Architects" (The Users) influenced the heroes and villains they found there for three years (thousands of years to the BZPB characters) for their own amusement. However, the Architect decided to mess around with the multiverse a bit more, and imbued Yon with some of his power, erased his memories of the encounter, and sent him to Bota Magna, where he ended up recreating Earth and Bara Magna.
He was later severely injured when Blackout invoked the Did You Just Punch Out Cthulhu trope.
He eventually recovered from said injuries, and had a nervous breakdown over not being able to do anything to stop Blackout. He shot Konta (User KoN's test account), only to be tackled by an army of MakutaKlak clones. He then decided to overthrow Black Six.