Testing out my own riddling and rhyming skills

[Laurh]

I come in without bidding
and leave again without remitting
For no one holds domain over my ways
I may bring salvation,
or absolute ruination
For no one is steering this chaise
You can rely on me with certainty
Even far beyond your eternity
For my one does not heed to your days

What am I?

- L. Elliot

[tiger_lily111]

Hi Laurh, & welcome! Interesting riddle. Here are some musings - 

Makes me think of 

Spoiler

Happenings on a cellular level - disease or mutation perhaps, though neither would be a great fit (from my limited knowledge).

Glucose would fit a number of your clues reasonably well, including chaise (chair conformation of glucose).

Another guess, in a completely different direction

Spoiler

Would be taxes. (Always certain.)

 

[SamHart]

Desert Rings in Shadow Of The Colossus
Shadow Of The Colossus

The world of Shadow of the Colossus is very detailed, though deserted. Fans of the series believed that there was a secret seventeenth colossus in this universe, although the developers have explained that there isn't one. However, they have announced that there is a special secret after all. The PS4 remake of the game did include a secret: if you find 50 gold coins in the game, you win... a bigger sword.

Nevertheless, the world itself is full of mysteries, and while it hasn't changed in the remake, fans are still trying to find clues to something bigger. One detail that remains unsolved is the desert rings. There are metal plates attached to the rings, and some of them are broken and others are not yet fully formed. There must be some connection to the world, but this remains unclear to this day.