Commanders and other units age one year every time Late Winter comes around, i.e. every 12th turn. At a certain age, called the max-age, they gain the Old Age attribute:

• (Str -x, Att -x, Def -x, Prec -x/2, Enc +x, HP -5%*x, CS -5%*x, MM -2x)

x is (potentially) calculated with: x = (current_age / max_age - 1) / 0.2 and rounded up.

So basically for every 20% of age rounded up the unit is over the max age, the unit gets one "stack" of old age. For basic humans, this starts at 50 years and increases every 10 years.

(ie. Old Age(65/44) = 48% over old age (x=3) = (Str-3, Att-3, Def-3, Prec-1, Enc +3, HP -15%, CS-15%, MM-6))

They also risk gaining an affliction every late winter, including deadly diseases.

Recuperation cannot heal afflictions from units suffering from old age.

Some units start with old age and most of the time will be shown in the recruitment screen. This can sometimes be false as it doesn't factor in age modifiers like magic sites or random paths. Every random path (shown as ) increases a unit's starting age, in addition to the max age modifiers from certain paths below.

A unit's max age is modified by the following (in order of priority):

• Undead creatures have their max age increased by 50% per point of Death magic.
• Inanimate creatures have their max age increased by 50% per point of Earth magic.
• Demons have their max age increased by 50% per point of Blood magic.
• Living units, i.e. not inanimate, undead or demon, has their max age increased by 50% per point of Nature magic.
• Living units also have their max age reduced 5% per point of Fire magic.

boosters/empower to remove old age or make recuperation work, accidental F old-age, old age making non-old-age afflictions unhealable

There are ways to "cure" old age.

• Twiceborn
• The Unaging Nature Bless. Note that this won't always be enough to make sacreds start young. Testing it with your nation is advised. It will still likely reduce the old age penalties, or allow nature randoms to start without the tag.