Ioun Stone

Ioun Stones are magical gemstones that provide various benefits to the to their user.

Description
Ioun Stones are named after the goddess Ioun, the Knowing Mentor. Each stone differs in color and shape. While worn, the stone orbits around the user's head and confers its benefits.

Varieties
The following types of Ioun Stones have appeared on Critical Role:
 * Ioun Stone of Reserve: The stone is a vibrant purple prism. The stone can store up to three levels worth of spells. Any creature can then cast the spell by touching the stone.
 * Ioun Stone of Fortitude: The stone is a pink rhomboid. The user gains a +2 bonus to their Constitution score, to a maximum of 20.

History
Around 802 PD, Jorlund Vohr, professor of archeology at the Alabaster Lyceum in Emon, led an expedition to the Frostweald, where he found a discovered a buried cache of Ioun Stones and a silver tablet with Celestial script. He subsequently sent them to the Lyceum, but by the week of his return, his findings and research, including the Ioun Stones, had all been stolen.

The Campaign of Vox Machina
An Ioun Stone of Reserve was initially owned by Tiberius Stormwind. He would later trade it to Scanlan Shorthalt in exchange for the Circlet of Concentration. Scanlan would later use the Ioun Stone to activate an obelisk dedicated to Ioun within the Frostweald, which pointed them in the direction of the sphinx Kamaljiori.

Campaign Two: The Mighty Nein
An Ioun Stone of Fortitude was at the The Invulnerable Vagrant, having been commissioned by the Cerberus Assembly archmage Jenna Iresor. She, however, had failed to collect it. Fjord managed to haggle with Pumat Sol for the stone, purchasing it for 5,500gp. He then gave the stone to Caleb Widogast

Owners
Reserve
 * Tiberius Stormwind (formerly)
 * Scanlan Shorthalt

Fortitude
 * Caleb Widogast