Withered

If a creature has been touched by a powerful source of necromancy magic, there is the possibility of having a limb shrivel up. The creature must make a Constitution saving throw, where the DC is 10 or half as much necrotic damage you take, whichever is higher.

While withered, a creature has disadvantage on Strength, Dexterity, and Constitution saving throws and ability checks. A withered limb is rendered useless until healed.

Treating a withered limb requires a DC 15 Intelligence (Arcana) or Wisdom (Medicine) check. On a success, the necrotic energy does not travel further into the body, withering the victim. Only one Intelligence (Arcana) or Wisdom (Medicine) check can be attempted per day for withered limbs.

A greater restoration or similar powerful spell will heal a withered limb.