Null Brooch

While wearing this brooch, you have advantage on saving throws against spells
and other magical effects. Additionally, the brooch has 3 charges. While wearing it, you
can expend a charge at will to cast the counterspell spell, as a 6th level spell. When
all of the brooches charges are expended, the brooch becomes a nonmagical piece of tarnished jewelry worth 10 gp.