Raw Essence

Description
Essence refers to two things in Ars Magica: Raw essence and reagents.

Raw Essence
Raw Essence is the magical power source that fuels the machines of Ars Magica. It is created by various types of nexi, such as the Essence Nexus. It is used to power blocks such as the Calefactor, the Caster, and the Magic Fabricator. It can be carried by Essence Conduits and deficit from moving essence can be mediated with a Crystal Pillar. Line of sight is not required to transfer raw essence.

Reagents
Essense can also be crystalized into item form. This is frequently used as a reagent for augmented spellcasting or as a component in creating blocks, items, and armors. There are currently 12 types of essence items. Each type of essence exists in opposition to another one. A player can read a book of affinity to gain the ability to cast spells of one type at lower cost and without requiring essences, but spells of the opposing essence cost more and require additional essence.