a cycle refers to a single iteration of the world. every cycle is run by one or two spirits, who are responsible for the creation and logic of the cycle (e.g. magic system, elemental makeup, physics, etc). since spirits handcraft every aspect of their cycles, their influence can be felt on both the micro and macroscopic levels.
for example, much of what ievafis (spirit of inspiration) had made for their cycle had been directly inspired by the different aspects of previous cycles. they and lystani would modify and implement parts of other cycles into their world, such as the wholly flexible magical of luterius’s cycle and a now-resort resident from abaddon’s cycle being the inspiration for one of their species.
cycles do not occur concurrently of each other (as in they aren’t timelines parallel to each other or a multiverse), and instead, they occur sequentially. near the end of a universe, the next spirit(s) are chosen to create the next cycle and are given time to prepare (as to prevent a rushed world development, especially when it comes to the world’s logic) as the current cycle reaches its natural end.
cycles are not a natural phenomena, but rather are the result of how cycle zero ended. when lux splintered and had their different traits separated into the individual spirits, the energy that gave them the power to mold the universe to their design also separated into smaller fragments, often referred to as “shards.” these shards are at the center of every cycle, with the energy they contain acting as their fuel. every time a new cycle starts, another shard is put into place by the inheritor spirit(s), and the rush of new energy overwhelms the current cycle enough to cause a reset—any remaining energy then combined with the new shard, so nothing ends up going to waste.
the way that cycles recycle the energy from the previous one is why physical items (e.g. objects, locations, etc) known as temporal artifacts are sometimes able to slip through the cracks and pass into the next cycle. the more cycles an artifact passes through, the less likely it’ll survive to the next though.
since cycles are reliant on what is essentially lux’s remains to operate, and because lux was not an infinite being, there is a hard limit on how many cycles will ever exist. the amount of energy lux had was innumerable but not everlasting, which means an end to the cycles will eventually be reached (even though the amount of time it takes is incomprehensible to think about).
a cycle typically lasts for a few trillion years, but its length can vary drastically depending on the amount of energy in the shard and the condition of its spirit(s). firstly, the shards did not break off equally, so some shards are made up of more energy than others. the amount of energy functions as a hard limit on the length of a cycle. however, even if there is still more energy in a system, a cycle can end abruptly if its creator spirit(s) is harmed in some way (physically or psychologically) since a spirit and its cycle are so intrinsically tied together, a cycle cannot continue to grow if its spirit is not fully present to aid it.
an important trait they have is their strict structure: once a spirit begins to shape a cycle’s energy into a specific form, it cannot be be reverted back to a prior state, but only refined. as well, their structure must be defined before the energy “settles” (like how clay hardens or ink dries)—after that phase, the spirit will not be able to change it at all (which is why rushed development is a concern—underbaked logic can be make or break for a cycle’s health). the development of a cycle will then be focused on smaller details—galaxies, planets, etc—whether they be handcrafted or born from the natural generation a cycle’s logic allows for.