"classic" Power advice: age control

[Bathawk]

hey all. A classic power in in fiction, usually when it relates to time, is the ability to add or subtract years to a characters lifespan, and was wondering if anyone had advice on how to accomplish this in GURPS terms?

An "easy" wayis to have an affliction that grants unaging (+150%) with unlimited duration (+150%, 'cured" by aging normaly). But this dosen't allow the simple reduction of years, or allow an opponent to be rendered helpless by reducing him to a toddler, or even infancy (we can probably skin the concept of reducing his age to pre-birth)

In the opposite range; a "toxic" attack with malediction, or an affliction that causes attribute penalties can work for advancing a persons age, but skips over using GURPS system for requiring aging rolls

The only other idea I have is a form of "Control" probably at the 30pt. level, where each level adds or subtracts a year for the targets age...a -20% limitation (or would it be -30%?) if it "only affects organics/living beings" would reduce the cost...otherwise i would say it allows it to "heal" or "damage" 1 point per level to normal objects

...of course then you would have to ask if a "beneficial" use gives a target youth and/or heals damage by 'reseting the clock"

Then the question is would you then need to add "permanent" to the already expensive cost to make the changes last