Dullahan Codex

The origins of the notorious Dullahan Codex are shrouded in mystery. Some legends claim it belongs to a dullahan whose head was taken by the Grim Reaper. Others attribute its creation to a powerful necromancer whose name has been lost to time. Whatever the truth, the grimoire has passed down through the ages, sometimes via mortal hands and other times mysteriously appearing among the possessions of its next target. It deserves its reputation for dooming those who possess it to die, but scholars debate whether the codex causes this fate or merely acts as its harbinger.

The Dullahan Codex is a jet-black tome bearing a single rune embossed on its cover, and it functions as a Freedom ritual aimed at ending this 10th-rank effect. (On a critical failure with this ritual, the codex adds all casters to its list.) You can redirect the curse by inscribing another person's name in the grimoire and succeeding at a DC 40 Arcana or DC 40 Occultism check. Doing so is an unholy act, anathema to many deities. If the curse is ritually ended or redirected, or the chosen victim dies, the codex moves on to a new victim.