Caveat magus: These are by no means the only tested rotes that can slow or reverse aging. Nor are they necessarily perfect. After all, any system sustained for too long is likely to deteriorate. However, these rotes have been grudgingly shared by allies for centuries and have proven more effective than most. They are somewhat ubiquitous - the foci and rituals may change from faction to faction, but the systems remain the same. Feel free to introduce these rotes with whatever name or methodology seems appropriate.
Shed the Years (••••• Prime, •••• Entropy, ••• Life, •• Mind, •• Time)
This is a "maintenance" rote preferred by mystics who can't bother with constantly active magics on their physical person. Some Verbena brew potions of youth; Sons of Ether boast of their Phoenix Engines. Whatever the outward trappings, this rote reverts the mage’s body to the state it was in nine years ago, effectively giving her almost another decade of life. Mystics who use this rote tend to perform it in a Horizon Realm, since the Paradox backlash could be intense indeed.
[This Effect requires five successes, and the difficulty is appropriately frightening. The pretense of high ritual usually aids the process, as does the presence of Tass. The mage temporarily halts entropy while using Life magic to rejuvenate her body. The Time Sphere helps the mage recall what she was like (not what she thinks she was like) nine years back, and the Mind Sphere helps her mentally adjust to the resetting of her brain without losing the memories of the last nine years. Finally, the adept must be a Master of Prime to fuel such an incredible regression to a younger, stronger state. Once the rote is completed, the willworker ages normally.]
Serenity of the Stone (••••• Prime, ••••• Time, •••• Entropy, ••• Life, ••• Mind)
This rote, a favorite of the Akashic Brotherhood, slows the aging process so drastically that the mage doesn't seem to age at all. Once performed, the mystic need not recast the rote time and again.
This rote can seem coincidental if the mystic secludes himself from regular contact with Sleepers. His Mastery of Prime creates a mostly self-sustaining Pattern that slows time and entropy. Life and Mind magic keep his faculties, both physical and mental, in proper working order.
The downside is that the mage is still a "thaumivore" of sorts, and must periodically refresh the Prime Pattern maintaining the Effect.
[Since this rote is more effective than most, the mage need only consume a point of Quintessence every week or so. If Quintessence isn't available, the mystic takes a Health Level of lethal damage per day, and begins aging more rapidly. In some cases, Paradox strikes willworkers at this delicate stage, rapidly withering them beyond their actual age. The cause is unknown, although the Chorus theorizes that the irregular ebb and flow of energy is an affront to Divinity.
This rote cannot stop aging, merely slow it to a crawl. The mage typically ages one year for every 50 she lives.]
What Price Age?
Immortality for a mage comes with a price. If the immortality rotes were not originally "vulgar with witnesses", then the mage suddenly accrues one or two points of Paradox the first time someone realizes that she is younger than she should be. If this has not happened over multiple castings of these rotes, then the mage may suddenly gain many points of Paradox.
Also, the mage becomes more out of touch with reality as the years progress. See Chapter Two - very old mages tend to lose their human perspective. Quiet, Jhor and similar fates are typical problems for ancient mages. Without the grounding of human contact, they quickly fall prey to madness.
Finally, immortality rotes can be cast on others. The problem, though, is that a mortal develops Quiet or Jhor as a mage would, but lacks the mage's understanding of how to deal with it. Mortals also suffer Paradox breakdowns over time when given immortality. Only specific transformations - such as the mummy Spell of Life - turn a mortal into something else, avoiding Paradox.