Okay guys it's
INDUCTIVE KONSTRUCTIVISM time

The BrikVerse came into existence with the appearance of the Deadly SpaceMan. The Deadly SpaceMan’s unprecedented awesomeness created a force of Kanon which expanded forwards and backwards in time, creating both a past series of events leading up to his appearance and a future set of events resulting from it.

In the course of everyday BrikVersal events, one event leads to another in sequence, in a manner familiar to Humans. However, as shown by the arrival of the Deadly SpaceMan, events that are particularly notable can gain the power of Kanon and force changes to events elsewhere on the timeline for the sake of Internal Konsistency. Changes to past events are called Retkons and occur by a process of Inverse Kausality.

The Deadly SpaceMan was awesome to begin with, and as the Deadly SpaceMen multiplied their power and coolness escalated exponentially. The unstoppable killers organized into warring DSM Empires that conquered the entire BrikVerse. The DSM Wars accelerated the creation and magnitude of Kanon so quickly that new events were Retkonning themselves faster than they could even occur in the first place, finally culminating in a recursive cascade collapse singularity. The entire BrikVerse timeline and everything in it exploded outward in an explosive Kanon ball.

Just as the DSM's arrival caused the creation of both past and future reality, the destruction of the BrikVerse created both preceding and subsequent generations of BrikVerses.
Incomplete and scattered chunks of the original BrikVerse's history and reality, known as Particle Kanons, acted as seeds for a new and Rekonstructed BrikVerse. Events and characters from the original BrikVerse Kanon reappeared in the new timeline, but not always in the correct order or locations, and the empty sections of history filled themselves in as best they could along slightly different lines than the original version.
Meanwhile, reverse-polarity AntiParticle Kanons traveled in the opposite direction, creating an earlier version of the BrikVerse to precede the original one. This Retkonstructed BrikVerse included no minifigs, only collections of strange, regressive creatures who seemed to only come into existence as potential ancestors to the minifig-kind of later BrikVerses.

Naturally, some Particle Kanons carried Deadly SpaceMen along with them, and the introduction of Deadly SpaceMen into the new BrikVerses had the same result as in the original: their influence caused escalating Kanon events until Infinite Kanon was breached and the new BrikVerses exploded as well, sending chunks of themselves forward and backward into Rekonstructed and Retkonstructed versions of their own, and even paradoxically re-seeding each other and the original BrikVerse from which they'd been spawned.
So there you have it! Easy enough for a minifig to understand!