Mana cannot fuel a ritual; it lacks the density of power needed to create the effects of a ritual, and disperses into the atmosphere too quickly to be used in one. Aether, however, is a perfect energy source for magical rituals, provided it is condensed into a small package (such as an Aether Crystal) and then steadily released into the ritual’s workings. This makes Aether Crystals a vital resource, as they are by far the most reliable means of powering rituals known to mortalkind.
Every ritualist taking part in a ritual can consume one or more Aether Crystals to power it. Each Aether Crystal consumed this way contributes +1 Ritual Power to the ritual, which is doubled if the mage in question has Mastered that ritual.
The maximum number of Aether Crystals that a mage can consume during a ritual is equal to their Aether Channeling attribute. The value of this attribute is determined by a number of factors, such as whether they’re a Mystic or Arcanist, how many levels of the Mana Well ability they have, whether they’ve drunk a Brightblood Elixir or similar, and so on.