Red Stone of Aja (JJBA Supplement)
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Wondrous item, artifact
This palm, sized red gemstone has been passed along a lineage of humanity's greatest leaders and rulers since time immemorial. Its unique composition and crystallization allows it to refract Hamon perfectly, which can imbue the undead with so much lifeforce that rather than dying, they become truly and completely immortal.
Hamon Refraction When a Hamon Warrior uses a Hamon technique while wielding the Red Stone of Aja, they may reduce the technique's cost to 1 unless its cost was already 1 or lower, in which it becomes 0.
Perfect Lifeform. A creature that is in some way a vampire but did not multiclass into the Sideshow class can don a Stone Mask laden with this stone to ascend to become the ultimate lifeform. Once achieved, they are resistant to all damage, except for radiant and necrotic which they are immune to. They are able to cast true polymorph at will on themself regardless of CR, and any resource pools (i.e. spirit points, hamon, spell slots, etc.) are doubled. All of their ability scores become 30, and their hit point maximum is doubled. If they had a regeneration ability from a vampiric source, it does not cease to function, unless they are at 0 hp (if a given condition). They may also use any feature they have seen.