Amulet of Great Power

This amulet is 1 out of 3 items that combine to give someone great power and the ability to cast Great Power spell, but by itself it is nothing but ugly jewery that gives you disadvantage on charisma checks and a -5 penalty to the DC of spells or other magical effects you create that charm a creature.

Notes: Requires attunement with 2 specific magic items to be useful