Azura's Star

This powerful gemstone originates from the Daderic Prince of Dusk and Dawn, Azura. It is gifted to her Champion or those she deems worthy of its power. When wielded by one blessed by Azura, Azura's Star functions as an all-powerful arcane focus. Whenever the wielder kills a non-humanoid creature(excluding constructs and the undead), they may attempt to trap the soul of the creature. The target must have been successfully hit by the Soul Trap spell in the last minute. Every successful soul trapped converts to a charge that the Star stores indefinitely. 

Azura's Star has an alternate form known as the Black Star, which has the ability to trap the souls of humanoids. The soul of a humanoid counts for two charges. Trapping the soul of a humanoid is considered an act of evil and partaking in such an act will result in a permanent alignment change, if the wielder is not already Evil-aligned. 

The charges may be spent to alter spells, spell slots, and fill component costs. The Star may be used once per turn as an action, and may only affect a spell once per use (EG, you can't restore a spell slot and substitute component costs to cast the spell in one turn). It cannot be used as a bonus action. The charges may be spent on the following uses:

• Partially or fully substitute the component costs of any spell (as defined in the spell's description), expending 1 charge per 100 GP
• Restore spell slots, costing 1 charge per spell level
• Change a single prepared spell for the day, costing 1 charge per spell level. Cantrips cost 1 charge

Notes: manifestation of Azura, Jewelry, Focus