| Category | Resources |
| Type | stone |
| Source | natural - Nessus |
Hellstones are the most resilient gemstones known, capable of withstanding the fiercest blows and weapon strikes unscathed. These gems emanate an internal, flickering radiance and inflict harm upon non-evil creatures (as well as half-damage to non-lawful evil creatures) with the slightest contact. Upon touching a Hellstone, the target suffers 1-4 hit points of damage plus 1 additional hit point per level of the affected creature (Fortitude save DC 16 to negate all damage). Also referred to as "Doomstones," these gems are exceedingly rare, found only on the world of Nessus. Prolonged exposure to these stones is believed to gradually shift one's alignment towards lawful evil.