Your Intelligence score increases by 2 and your Wisdom score increases by 1. An ability score cannot be increased beyond 22 this way. You become an Undead in addition to any other creature types you are. Spells and abilities that state effects or conditions specifically regarding Undead of a specific CR have no effect on you.
If a spell or ability other than your own would cause you to gain Hit Points, you gain that many temporary Hit Points instead. If you are reduced to 0 Hit Points and fall unconscious as a result, any healing you receive will stabilize you and leave you on 1 Hit Point and unconscious. You stop aging. You are immune to any effect that would age you, and you cannot die from old age. You do not require air, food, drink, or sleep.
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