Baffled by old age

[Jack_Trowell]

Death magic does not increase the old age, but is supposed to (greatly ?) reduce the chance to get afflictions from it.

Death/growth scales are also supposed to increase or decrease the chance, but much less I think.

Note also that fire mage slightly lessen your old age :

Normal human mage : old age at 50 years old
Same with N1 : old age at 75
Same with F1 : old age at 4X something

Note also that earth is used instead of nature for lifeless beings, and maybe Death for non lifeless undeads or demons.

[Thilock_Dominus]

Death magic does not increase the old age, but is supposed to (greatly ?) reduce the chance to get afflictions from it.

Well, if you're an undead, death magic will increase old age.
I have an undead Shadow Dragon Pretender (mod), with default old age at 2500 years. By taking 9 death in magic path the old age is set to 13750 years.