Magical Anomalies

Magical anomalies are places where something happened. Something so extraordinary that reality itself was damaged. Light and Dark underwent a partial merger into a form similar to a Primordial Chaos. Causing vast changes to even most basic laws of reality, not to mention geography and magic.
On one hand, magical anomalies are a major threat requiring permanent attention of many organizations to contain them. However, they are also a basis of modern technomaturgic industry (together with Dungeons), being an important source of power for the countries that control them.

The genesis of anomalies

There are six basic causes of a creation of magical anomalies.
Negatization is a long term process of a deformation of local Dark due to events charged with negative emotions. For example painful deaths. Anomalies created through Negatizations tend to be among those most devastating for ones sanity. Unspoken Isle being a good example.
Imprint is better described here. In short - they are created when something frightful and insanely powerful makes its nest somewhere, its sheer presence deforming Reality and Unreality around it to better suit it. An example can be a Freezing Sea anomaly, most likely created by influence of Nythrathril.
Puncture anomaly is created when another world partially connects with Gates of Eternity, its foreign magic and Dark causing a disturbances with the local reality. The more alien the another world, the more extreme the anomaly (with Glass Forest being a great example).
Infuse anomalies are created when some magical cataclysm causes heavy magical irradiation, opening the Light to the influence of the Dark. Great example can be Bone Mountain in Ceveria, where archenemy of local pantheon fell when he was cast away from the Heavens.
Distortion occurs when something significant happens. An artifact is destroyed or hidden away, an important person dies or does something... important. Most of them are almost undetectable, but when distortions accumulate (or something truly extreme happens) they can become something much more.
Others are in most cases one of the aboves, but their true nature is yet to be discovered by researchers.

Geography

Each magical anomalies includes a vast array of special locations... that are literally limitless in number. After all anomalies are places when Dark infuses Light, meaning that some of its special qualities begin to influence the Reality.
Dark never forgets. Everything that it swallowed, remained there for eternity. When anomaly is created, an echo of what once was begins to reach Material World. The remains of old-forgotten civilizations resurface, together with mystical artifacts, archeological discoveries... and ancient magicks.
Items - or even creatures - that once become a part of Dark, can be ejected from it by the anomalies a thousand times. One sword can be found by a million of adventurers - but its discovery remains something random, as Dark waxes and wanes in a way that is completely unpredictable.
Anomalies would be a literal mines of mystical artifacts if not for the influence of the Material World as a whole that considers them a foreign objects. The farther from the source of distortion and anomaly itself, the more the space itself bends before laws of physics rather than of magic. The closer to the center, the more powerful things are materialized and can be found.
Additional exceptions are places that are much more reflected in the Real World, for example permanent outposts inside the anomaly. It is impossible deep inside them, but on the fringes the situation is different. Once created outpost is geographically anchored by its inhabitants belief that it exists in that very place. The same happens with some more or less important locations - the more people believe them to be somewhere (for example 'in the south part of the anomaly') the more stable it is.
Even roads drift - while they still lead from point A to B, the parts between them drift. They are anchored merely by the belief that they connected two points... but the distance and exact path is perpetually changing.

Natural Resources

There are several chief reasons for adventurers to head into magical anomalies... and risking their lives.
Daemons, a strategic resource that defines the number of magicians and sorcerers a country can field. Daemons much easier manifest in anomalies, meaning that they can be hunted and used
Raw Materials. Reality in anomalies is influenced by social consensus. People believe that anomalies are a place of many treasures... which includes a vast number of raw materials, irradiated with magic into new and amazing forms. Ores, wood, crystals, stones... there is a reason why many countries keep regular mines in anomalies, staffed by prisoners. This also includes a vast array of alchemical ingredients of great value.
Aether - a liquid magic. Absolutely required for any technomagical industry to work. It can be gained from creatures slain in anomaly, or by certain places where the anomaly is the thickest and it literally floods the Reality.
Unique Magicks. Because some anomalies have a unique schools of magic that draw from their unique magic. They can be learned only there. And tend to be very powerful and deadly.

Type

Region