Greater antidragon aura

Greater antidragon aura was a protective spell used by clerics.

Effects
When cast, this spell created a protective aura around the targets that glowed with a phosphorescent green. It provided extra protection against attacks and and resistance to spells from all sources, not just dragons and their ilk. For them, it also provided significant shielding against their spells. Additionally, it protected against any attempt by a dragon to possess or influence a creature's mind, as with protection from evil. Finally, if dragons and related creatures did manage to strike a protected creature, then they would suffer a loss of strength.

This spell increased the strength of

Components
In addition to verbal and somatic components, the spell required a focus: a container, such as a reliquary, that held a sacred relic. The relic was often a piece from the sword of a dragon slayer. The sacred relic had to have a value of at least 500 gp.