Niflheim
Niflheim is the northernmost location on Eon, and considered to be one of the three pocket dimensions that are affixed to the main dimension Eon resides in. It's also known as The Land of Mist, as the combination of the magically attuned gemstones and the inhabitants cause a magic, neutral mist to permeate throughout the entire realm. While the realm itself is far up north, and thus can have ice, it should be noted that it is not entirely icy. Niflheim's entrance is typically pretty icy, but the mist, cold temperature, and structure is caused by the abundance of mythril in the entire realm.
Helholtt is directly south of Niflheim, and while it's hard to access unless one has a rune seal to break the pass, many mortals have managed to end up in Niflheim by complete accident and then recalling a "heavenly figure" saving them and putting them in a city somewhere in northern Helholtt.
The queen of the lands is Queen Mab, also known as Sinmara as her ancient name.
This realm is also the only realm, besides the mortal plane where Shimmer can actually call it home. Many of them live and thrive here if they aren't naturally born in the mortal realm, or if they were birthed directly from Queen Mab herself. Some Shimmers have been said to be as tall as a mortal from Eon as well, something that hasn't been studied or researched enough to confirm it being true or false.
Geography
Nifvlheim is known for being extremely rich in mythril ore and composed of nothing but solid rock, water ice and gemstones. The rocky and ice structure of the realm causes an abundant of mountains so high they can pierce the clouds above. The land constantly generates a mist that may either be as low as someone's ankles, to fully swamping a person's body and hiding them. While this remains consistent throughout the realm, there are parts of Niflheim that differentiate quite a bit, such as being composed much more of gemstone rather than rock (causing the large amounts of mist), or being nothing but ice, which one may notice upon entering the realm from the most northern point of Helholtt.
The mist in Niflheim is relatively harmless, and is just a side effect of the magically attuned gemstones subliming the excess off of their structures. And while the realm is made somewhat of ice, the temperament of it is actually very comforting. Some researchers who have made the trek to Nifleheim had wrote about taking off their gear made to withstand blizzards, as they became too hot while there.
The other interesting bit about Niflheim was the fusion of Jotunheim with it during the Voidseed War. While a magical ice blast had caused the geography to forever be changed to its icy and rocky look for part of the realm, the other realm inherited the giant's land and half of it became this beautifully prairie-land like area with lots of mountains. This area, while beautiful, is hard to reach as it's further into Niflheim, and where one would most likely find Jotunn there. Normal fauna and floral life grow there, and the lifestyle is shown to be hunter and farmer based, with taking care of the land and animals as well. The Yggdrasil grows just as extensively here as well, with the roots exposed around Jotunn civilizations and allowing for them to make their magical ink relatively easier by mixing the dew with properties (which gives them ridiculous strength). The dew and roots being exposed adds more magical influence to the land as well.
The downside of the realm is the slowly poisoning part of it, called The Dark Realm. Due to the side effects of Faeries having moved into the realm of Vanaheim, this has caused their magic to have an adverse effect of causing the poison to become a poison mist, something that the queen is looking to correct before it takes over her realm and ends up spreading directly onto Eon through Helholtt. The creatures that naturally live in Niflheim also become effected b the poison mist and become much more aggressive and give off poison gas, which only spreads the blight further.
Localized Phenomena
As mentioned previously, the mist is the most abundant and well known feature of Niflheim, and is the reasoning behind its name as well. The mist being magically attuned has gotten researchers and scientists interested in the possibility of harnessing it and creating very clean energy that doesn't rely on draining the planet's natural magic to dangerous levels.
The mist can react to any kind of magic and using rune magic can have an effect on it that proves to be effective in both combat and resources for medical care. For example, combining it with fire can cause a violent explosion within the area contained with the rune magic, while combining it with water can create a healing mist that can be sprayed over a person, or inhaled to cure them of any ailments they may have.
Queen Mab is able to utilize the mist personally for helping conceal the realm better, or switching the use of it to poison to healing magic as needed as well. Most of her children reamaining in the realm can also do the same thing, which is why they're stationed around possible entryways to prevent miscreants or curious persons from wandering in.
Another interesting phenomena that Niflheim has is the constant aurora borealis in the skies during the night time, due to the mist interacting with the magnetic particles generated by the planet. These can even be seen in the day time, especially after a gem rainstorm has happened, where most mist is able to interact further with the environment. It's said that the aurora borealis is absolutely breath taking, and to be able to see them is a blessing in itself due to the circumstances of the realm.
Climate
The climate on Niflheim is reasonable - the temperature always remains at a chilly but comfortable 60 degrees, perhaps even 70 - and yes, the ice will still remain even it being double the temperature for freezing. This is due to the mythril properties of the realm creating some sort of magical barrier that protects the ice from fully melting, but also not causing the realm to plunge to drastic temperatures that could kill someone not covered up.
The one cosnistency with Niflheim is also the lack of weather patterns or related phenomena. The realm is constantly mostly cloudy, with some breaks in the clouds showing off a gorgeous blue sky dotted with starts and galaxies. Though there doesn't really seems to be a sun anywhere in the sky, the realm is still lit up from a light source, and due to this magical barrier mentioned before over the ice, it doesn't cause snow glare to mortals.
Sometimes it may rain gemstone in the realm, but it's typically rare, and it may be dependent on Queen Mab's emotions at the time as well. These gemstones will end up melting or evaporating into the ground, which may cause more mist to spring up as well.
Fauna & Flora
The flora and fauna life in Niflheim is fascinating, as at first glance it doesn't seem to be anything living there besides the Shimmers. But upon closer inspection, there are creatures made out of the mists and rock of the land, taking on the characteristics of creatures from the mortal realm to some capacity, such as wolves or even birds. While this may be normal in other realms such as Vanaheim or even Alfheim, Niflheim originally was pretty desolate due to having almost no floral life naturally. Some researchers hypothesize that Queen Mab's constant trips to the mortal realm has her yearning for life in her own realm, so she creates it using her mist magic to emulate life. The same also goes for any and all floral life, though its noted that some flowers are actually natural to Niflheim, such as the mist lily being compacted versions of the mist in the realm, but brought to life through a flower. It shares its same properties with the mist, and are the easiest ways to harvest it without damaging the realm extensively.
Deeper in Niflheim, there are other creatures living in the realm due to the fusion of Jotunheim. There are various creatures of all types, including Frost Wolves, which can act as familiars to Jotunn.
Natural Resources
What makes Niflheim so famous and sought after is the overflowing abundance of precious metals and ore that come from the lands, something that is almost impossible to get due to how the realm is set up, Queen Mab entrusting her children to protecting, and other hazards that deem the journey far too dangerous (such as Helholtt itself being a blizzard terrain that have caused many deaths to travelers).
The most famous, rare, and well wanted resource that originates from Niflheim is mythril, which is what Queen Mab is entirely composed of. This elusive metal is strong, while also being lightweight, and can channel powerful magics into itself, while also remaining non-elemental. The non-elemental factor is super important as it can be used for literally anything, making its versatility priceless. This is especially why Scholar tools or Hunter weapons made of mythril are so expensive on Eon; while it's considered luck to find a cache of mythril to be able to use, it's still a rather rare resource that's virtually cut off from access through their queen for both protective and preservative reasons.
The other gemstones that can also make up Niflheim in small amounts besides mythril are just as sought after as well, but not as much as the main metal.
History
Like all the other realms on Eon, Niflheim was primordial soup that had no way of formation when the planet was at its baby steps of forming correctly. As the planet began to cool down, Niflheim began forming much faster than the others, and with the abundance of resources, began to take shape as being the north pole on the planet. Strange as it was to be connected to the mortal realm compared to the other realms having noticeable difference, this was shaped further by the birth of the first Sprite, Queen Mab. Mab was just as tiny as the other sprites at first on Eon, but quickly grew to her enormous size from consuming the resources as fast as they were forming.
Niflheim was then formed, but it was not always icy nor frigid. The land originally was just gemstone and rock with some permeation from the mist. When a large, continent scaled blast that made the entirety of Helholtt and even Skaalsborg and Ni'Avan become effected due to the ice magic used, Nifleheim was effected just the same. Some rock was replaced with ice while ice in general grew over in areas and concealed more of the precious resources. While this wasn't upsetting to Queen Mab, as she had participated in the war that caused this to happen, it was a surprise to come back home to her land of mist now also being the land of ice.
Besides some of the historical notes made above, most people are unsure of the full length of history Nifleheim has to offer. The queen and her subjects keep their history and secrets very well against strangers, and most people who find their way in Niflheim are quickly escorted out and teleported into the closest, northernmost city of Helholtt for safety.
