Events, creations, and storylines in the BrikVerse have different degrees of reality, determined by the strength of one or more Humans' belief and interest in them. This belief grants these elements of reality a form of ontological mass called Kanon. Exciting, memorable, and awesome elements tend to gain a high degree of Kanon, especially as they influence and become entangled with other Kanon events and storylines. Boring, forgettable, and lame elements have low or negative Kanon, especially as Humans work to rationalize them out of existence with Retkons.
In the shared reality of the Far-Ums, high-quality photographs are the most important factor in generating Kanon, as even the most awesome events can fall victim to the ancient minifig curse "Pics Or It Didn't Happen."
The more Kanon an event has, the more strength it has to force Internal Konsistency on other parts of the timeline. The appearance of a sword that has slain a thousand demons requires the creation of not only a past battle in which a thousand demons were slain, but the creation of a race of demons in the first place, and the world from which they sprang. A large Kanon means that there are Humans with the interest and motivation to imagine these new elements; a tiny Kanon means that the Humans just ignore these details or hand-wave them away without further thought.
With enough power, elements of new Kanon may alter or obliterate the details of existing lesser Kanon. This normally serves to make the BrikVerse progressively more Ossum, as awesome elements replace less awesome ones, but can be accelerated to an unsustainable degree. The destruction of the original BrikVerse, B.R. 1,977, was brought about by Deadly SpaceMen accelerating the creation of new Kanon to the point that the Kanon divided itself by zero, Retkonning itself into a infinitely recursive cascade collapse known as the Explosive Kanon Ball, seeding the creation of all preceding and subsequent BrikVersal Rekonstructions.