Magius

Magius is a human ability that allows individuals to conjure and manipulate various elements. The possession of magius is highly valued among the nobility, who look down upon those without magius and consider them unworthy of a place in society.

Properties
Magius is innate in most nobles. Humans born without magius are labeled as "incompetent." Demons also do not have any innate magius. All wielders of magius possess the ability to use two different elements: the first being light, which is common amongst all magius users, and the second element being unique to each individual user, such as lightning, ice, or water. Light magius is particularly useful when fighting demons, as they're weak to such power. Upon death, a human with a secondary elemental magius leaves behind a crystal holding this power, which enables anyone holding it (including demons) to utilize that particular magius.

Weaknesses
A major weakness of magius is its detectability. Anyone with a magius can detect the presence of someone else wielding magius, so long as they are paying attention for one, the presence of any assassin would be given away. However, this sensory ability itself also has a downside that renders it a double-edged sword, as weaker magius is much more difficult to detect. Anyone without magius, or with a very weak one, would be able to evade detection and catch targets off guard. Another weakness is that magius can be stolen, as all magius wielders with a secondary element possess a crystal that allows those holding it to use the power. This means that incompetents and demons, who normally cannot use magius, are able to wield magius if they somehow acquire a crystal. The biggest weakness of magius is not with magius itself, but the overreliance its wielders have on it. This often causes nobles to judge a person's worth entirely based on how much magius they have rather than who is actually wielding it. Additionally, wielders have been found less athletically capable than most incompetents, such as Deor Fluenti. Most wielders also don't appear to have any kind of alternate strategy to fight should their magius is overcome.

Known Spells
Most users need to say the incantation for a spell in order to use magius, the exception being those loved by the Gods. It has been observed that no incantation is needed for secondary elemental magius. Spells used without an incantation have also been observed to be more abstract than spells used with an incantation.

Here is a list of all currently known light spells.