Mordenkainen's defense against lycanthropes

Mordenkainen's defense against lycanthropes was a spell that improved the chances of surviving an attack by lycanthropes.

Effects
The spell prevented the caster or a targeted creature from contracting lycanthropy. This was only successful if attacked after the spell was cast, as the spell did not offer this protection on a creature who was attacked before casting.

Components
In addition to verbal and somatic components, the spell required a material component, a moonstone with a value of at least 30 gp. It was crushed during casting.