D&Dtools1

Upon completion of the spell, you exhale your last breath and accept a brief embrace from death.

You gain many of the traits common to undead creatures. While the spell lasts, you have immunity to mind-affecting spells and abilities, poison, sleep, paralysis, stunning, disease, death, extra damage from critical hits, non-lethal damage, death from massive damage, ability drain, energy drain, fatigue, exhaustion, damage to physical ability scores, and any effect requiring a Fortitude save unless it is harmless or affects objects. You need not breathe, eat, or sleep.

Like an undead creature, you are damaged by cure spells and healed by inflict spells.

You don't actually gain the undead type from casting this spell.

Material Component: A finger from a zombie.