Vertiago's Law

Vertiago's Law is a principle of magical interactions with its nearby environment, specifically with environments that have a high concentration of dry ice. Simply put, the dry ice causes an interrupted spell to be reflected and repeated. The best theory as to how this is possible is that dry ice's makeup causes it to be unwilling to absorb the magic like most other substances. In most normal cases, the magical energy from an interrupted spell will simply be absorbed back into the world.

Discovery of Vertiago's Law

Vertiago's Law was discovered when an explorer entered one of Kreshniva's many naturally-forming dry ice caves and came across a rather perplexing scene: a man frozen into an ice statue that continually crumbled and reformed itself. The ice would crumble, but before the crumbling could reach the man's shoulders it would suddenly stop, and eventually the body would re-freeze. Upon investigation, the man had died in the middle of casting a healing spell. Yet somehow, his spell was perpetually repeating itself.
At first this discovery threatened to undermine everything known about magic and its interactions with the caster's surroundings. Until that point, the magical energy from interrupted spells were believed to eventually return to the environment. However, here was a man-statue with a healing spell repeating despite him being dead for an unknown amount of time - perhaps only a few days, perhaps a year or more. Researchers came to the site and removed the statue from the cave, and found that after some time the spell faded away like interrupted spells normally do.

Experimentation

Following this discovery, the researchers took some samples of the dry ice out of the cave and into their studies, hoping to find some kind of clue in the ice. First, they tested uninterrupted spells, to find out whether the interruption had any part in the strange behavior. This taught them that a completed spell would not produce this same effect. Then they moved onto testing different spell types: could Single Cast spells or Incantation spells also do this, or was it only Continuous Cast spells? Eventually they found that, while a Single Cast spell could be repeated for a short time, Continuous Cast spells could be repeated for a very long time. Incantation spells were found to be unaffected by dry ice, curiously enough. In effect, while a firebolt spell or a lightning bolt spell may be repeated for a short time (about 20 minutes), a spell that has to be continually casted in order to be effective (such as a healing spell) can last a lot longer (some reports claimed several days, while others claimed several months).

Naming

Unfortunately, neither the explorer nor the researchers knew the unfortunate man who had turned himself into a statue. The researchers spent several months asking around the local towns and villages to find any friends or relatives who could identify him, but nobody was found. Without that information, the researchers also didn't have a name for the unlucky man. Eventually, they decided to give him a new name: Vertiago, from a Kreshnei word meaning "surprise, unexpected".

Manifestation

Some interrupted spells' magical energy will appear to reflect within the dry ice enclosure, while others will just bounce off of any dry ice they come into contact with.

Localization

Verti's Law mainly shows itself in the regions associated with extreme cold, such as Saiba, as well as the Tratia Archipelago, and the southern portions of Stonad and Kruthia.

"This stuff is harmless, as long as you don't directly touch it, breathe near it, or bounce any high-power spells off of it."

— Professor at Saugarth's Academy Of The Arcane

Other Interesting Things to do with Dry Ice

Ice Lantern
For a short time, you can create an ice lantern using this property of dry ice. Just shape the dry ice (don't touch it yourself, use magic to do that) into the desired shape, and then aim a spell into the "lantern" (fire, light, and electricity are the most commonly used elements) and interrupt the spell before it can be completed. Then just seal off the "lantern" with some more dry ice.
The lantern will only last for about 20 minutes, so don't plan on using it for any long expeditions or journeys.

Ice Grenade
The creation of an ice grenade is almost identical to the creation of an ice lantern. The difference is, you'll want the ice to be somewhat thinner for the grenade, so it explodes upon impact. Just be careful not to throw it at anything you want kept intact/alive.

Type

Natural