Embrace of the Hollow Soul

You infuse a willing creature with necromantic essence, transforming their physical form into that of a spectral undead. The target retains its mental faculties, alignment, and class features, but their body becomes pale, translucent, or shadow-wreathed—reflecting the type of undead they temporarily resemble (wraith, revenant, or similar).

While under this effect, the creature gains:

• Type change: Their creature type becomes undead, in addition to their original type.
• Gain temporary 15 HP
• Immunity to necrotic damage.
• Advantage on saving throws against being frightened or charmed.
• Can be affected by spells and effects that target undead (such as Turn Undead or Control Undead).
• The creature’s attacks count as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage.
• The creature gains Darkvision out to 60 feet (or +30 feet if it already has it).

However, while transformed:

• The creature is vulnerable to radiant damage.
• The creature cannot regain hit points from healing spells (only regeneration, rest, or necromantic healing effects like vampiric touch or false life).
• The creature has disadvantage on Charisma (Persuasion) checks against humanoids unless it conceals its condition (e.g., wearing a hood or mask).
• The creature may be repelled by consecrated ground or holy effects at the DM’s discretion.

At Higher Levels.

When you cast this spell using a spell slot of 6th level or higher, the duration increases to 8 hours. At 7th level or higher, the creature also gains a boost on temporary hit points equal to your spellcasting ability modifier + your spell level.

Flavor Notes for Ravenloft:

This spell can be seen as a rite used by righteous necromancers to "mask" allies against undead foes or survive in cursed places. It blurs the line between life and death—just as Ravenloft itself blurs the line between heroism and corruption.