Halo of Equilibrium

There is no 'give' without 'take'. For once, let us use that to our advantage.

— uneasy dwarf

The halo of equilibrium is a dwarven invention from Fjolkandr that was originally born in an attempt to mimic the undecaying nature of Feidísfolk architecture. It is, in essence, a ring of carefully-carved stones that must be placed in perfect arrangement around an area. Once activated, the Halo will hold everything inside it in stasis - and in turn, rapidly advances aging for an equivalent region external to the Halo.
Haloes of equilibrium are fantastic for protecting artifacts from the ravages of time, which is their primary use, but can also be used as a defence mechanism due to the rapid aging effect. See, not all haloes affect sapient beings. The majority are created to intentionally only consider non-sapient life for its fuel; mortal lives are not at risk near these areas, and may be able to enter the stasis field without being affected by the halo's power.
Some, however, are created to deliberately target sapient life over all else. Mortals approaching these rings may find themselves rapidly suffering from magical aging and deterioration effects, their lives stolen from them in seconds-to-minutes before they can even approach the artifact they seek. These traps are often baited with items that rapidly decay placed inside their halo, causing the magic to have a far more intense effect on intruders than it might otherwise.

Discovery

We tried, tried, tried... and tried again. We'll get closer someday.

— member of the inventing team

The preservatives and enchantments used by the Feidísfolk have long been a questionmark in the books and scrolls of history. There is no doubt that protecting their belongings and homes so well brought the Feidísfolk much prosperity, with how much work it would have saved them. Homes would have needed less upkeep, clothes would only need mending when damaged, and weather would not destroy dropped scrolls or corrode dropped weapons so easily.

Carving Runes by Hanhula (via Midjourney)

There have been numerous attempts to duplicate this magic exactly, to no avail. It is strongly assumed that the Feidísfolk were aided by fey magics, and thus the exact enchantments or alchemical brews they were able to formulate are now unavailable. It is also possible that their abilities relied on the use of plants or similar that were once common in eastern Iskaldhal that are now extinct due to changing climates, weather patterns, and evolutionary differences.
Haloes of equilibrium were discovered in an attempt to bring the properties of fairy rings into an experiment by a small team of inventors led by the ever-curious Fylla Brahnrod. The team of 6 thought that by engraving abjuration runes to protect, transmutation runes to encourage change (or, well, lack thereof), and necromancy runes to decay would shield the object at the centre of the ring, and would alter any decay it experienced into further protection. They did not count on the ring of stones interacting oddly with itself.

Instead of merely shielding the object at the centre, minute details in how the runes were carved bent their purpose. Instead of necromantic decay being used to keep decay away, necromancy instead connected with the abjuration to form a loop via transmutation's power. Decay caused would be turned into energy to power the protections needed. The halo worked to prevent decay - but in that first experiment, two of Fylla's cohort were killed by the unexpected halo of destruction around their experimental area.
The experiment was replicable, and over time, became better understood. The rune systems required were vastly simplified, and the secret to how exactly one created the haloes was locked away in Fjolkandr's vaults. With the danger of the sapient-focused haloes, it was simply not ethical to share the knowledge with all.

Utility

Museums love this stuff. It saves so much time!

— museum curator

As the haloes can be scaled to virtually any size, their use is reasonably common around the many sites of interest in Fjolkandr. Artifacts at risk of being lost, especially those from the nation's early years, are regularly placed into small haloes within a watertight sphere to protect them until appropriate study can be made.
They're also common in museums, vaults, and the like, where decay may be a serious issue. Some food-producing farms are built within haloes to provide the nation with a source of risk-free food in case of calamity.
Use as a trap is common in some of the more violent dungeons and ruins around, and is typically done by powerful but paranoid folk. As haloes of equilibrium are relatively easy to break - through breaking their stones - they are not the most effective long-term trap, but make for a nasty surprise in combination with others. They could also be used to preserve life in critical situations - but if anyone has tried this, they haven't shared the results...

Treasure by Hanhula (via Midjourney)

Parent Technologies

• Abjuration

Preservation by Hanhula (via Midjourney)

Inventor(s)

Fylla Brahnrod & co.

Access & Availability

Widely known of, but heavily restricted. Applications must be clear on use, scope, and duration.

Complexity

Reasonably complex to create; easy to use.

Discovery

Discovered mid-4000s in Fjolkandr by Fylla Brahnrod's cohort

Related Species

• Dwarf

Similarities

An unnerving similarity exists between haloes of equilibrium and the feared Gate of Dust. Haloes are essentially protective circles that equalise their protection by decaying the area around them.
The Gate of Dust sits at the entrance to a dead area, circular in shape. Its forsaken grove is an area where decay consumes all that enters - including mortal life, often inducing extreme despair on the rare fool to wander in.
After the invention of haloes, there was much questioning on whether the Gate of Dust could have once been part of a halo, or whether the magics both used could be similar. Nothing has ever been definitively proven; those who try to find a link usually end up dust themselves.

I hear that the living can be preserved too, in the ones that draw life. Someone's going to do sommat nasty with that, mark my words...

— prophetic dwarf