One cannot stay too long in Astral Space. The body withers while the mind is at play. This spell nourishes and refreshes a mage’s body from within the astral, lengthening the period an astral traveler may go without returning.
The spell’s target number is equal to the number of days the mage’s real body has gone without nourishment. The spell makes up for lack of food and water. Air, too, though if the spell has to provide oxygen, the mage has immediate problems to worry about.
Mysterium Rote: Feeding the Cavernous Soul
Serious mystagogues cannot be bothered to leave their research in Astral Space for their body’s needs. After all, one might never find a way back to this astral realm. They use this rote to stave off starvation and thirst a few more days and keep to their studies.