Mycontil's last resort

Mycontil's last resort was a spell unique to Halruaa.

History
This spell was rumored to by used by Mycontil himself during his final stand against the Dambraii invaders, among them the Arkaiun barbarian chieftain Reinhar I.

Effects
This spell converted every spell memorized by a wizard into pure magical energy, allowing for an extremely deadly strike to every creature standing with 30 ft. (10 m) of the caster.

This spell even affected creatures with magical resistance, but with less power.

The caster risked their life when casting this spell. If they were able to resist the deadly magic, then the caster was permanently weakened, often falling into a prolonged coma for several weeks.

Components
This spell required a finger bone of an archmage to cast. Before casting, the finger bone needed to be prepared using a special ritual that lasted several days.

Materials needed for the ritual included:
 * diamond dust worth at least 5,000 gp
 * platinum ring