Ritual

Rituals are invocations of the deepest and oldest magic. The kind used to forge the world. The kind used in the distant past to level mountains and fell empires. Rituals are a petition to the very laws of nature themselves. Rituals are not something that you can just fire off during a round of combat. Spells require fuel, but rituals require offerings.

Rituals are nowhere near as prevalent as spells — they're complex, powerful, and dangerous. A mage may spend the majority of her life creating a ritual. To learn a ritual might be the very goal of a role-playing campaign. A ritual might end a drought, destroy an ancient evil, or grant immortality itself.