Potara Earrings

Equip X - Exile target nontoken creature you control and pay X, where X is the exiled creature's converted mana cost. Place exiled creature under Potara Earrings. Reduce
X by 1 for each creature type shared by exiled and equipped creature

Equipped creature gets +x/+y, where x is exiled creature's power and y is exiled creature's toughness.
Equipped creature gains all abilities of exiled creature.

When equipped creature leaves the battlefield or when Potara Earrings becomes equipped to a diff