Aumvor's Fragmented Phylactery

Prerequisite. You must be a lich with at least one phylactery. A living creature that attempts the spell takes 10d10 necrotic damage that cannot be reduced, and the spell fails.

This rite does not create lichdom. It multiplies the vessel that already holds a lich's soul.

When you finish casting, choose one mode:

Fracture. You touch one object that is already part of your phylactery. It splits into a number of separate fragments equal to 1 + your spellcasting ability modifier (minimum 2). You choose each fragment's form: a piece of the original (a bone, a gem shard, a plate from a reliquary) or a new Tiny object of similar quality. Your soul is bound equally to every fragment.

Bind. You touch a number of unattended objects up to your spellcasting ability modifier. Each becomes a new fragment and joins your set. An object must be exquisite, solid, not wood, and worth at least 5,000 gp (a rare or rarer magic item also qualifies). You cannot bind another creature's phylactery, a sentient item with a conflicting will, or an artifact the DM rules is beyond this spell.

Repeat castings. You may cast this any number of times. Each extra casting can add a number of fragments up to your spellcasting ability modifier. Aumvor repeated it until all 206 bones of Dethed's rune-scribed skeleton were independent phylacteries.

Rejuvenation. While at least one fragment exists, you have a lich's Rejuvenation trait. When your body is destroyed, a new body forms in 1d10 days within 5 feet of one remaining fragment. You choose which fragment if you know of more than one; otherwise it appears near the nearest fragment on the same plane. If none remain on your current plane, the body forms on the plane that holds the most intact fragments.

You can be permanently destroyed only when every fragment is destroyed.

A fragment. Tiny magic object unless you kept a larger form. AC 20; 40 hit points; immunity to poison and psychic damage; resistance to bludgeoning, piercing, and slashing from nonmagical attacks. Immune to dispel magic. Cannot be targeted by telekinesis unless the caster's spell save DC exceeds yours.

It does not work as a magic item for anyone else. Another creature that tries to attune to a fragment that is also a magic item fails and takes 4d10 necrotic damage.

Destroying a fragment: reduce it to 0 hit points, then smash the remains with a magic weapon or consecrate them for 1 minute (treat as turning undead against your spell save DC). The DM can give a specific fragment a unique destruction condition instead.

Veil of the Undying. Detect magic shows only a faint, untyped aura unless the caster succeeds on an Intelligence (Arcana) check against your spell save DC. Locate object, locate creature, and similar spells cannot find a fragment unless the caster has handled that specific fragment or is a god acting on the same plane. Legend lore can reveal that a soul is divided, not where any piece lies.

The soul's strain. Each time you finish this spell, you take necrotic damage equal to 5 × the number of new fragments. This damage cannot be reduced, and those hit points return only via wish or by feeding a soul into your phylactery set. If the damage drops you to 0 hit points, you are destroyed and begin Rejuvenation; the new fragments still form.

If you have more than ten fragments, you have disadvantage on saving throws against effects that turn undead, and a priest who knows the rite can sense the divided soul within 30 feet.