Enchantment Breaker

Wisdom: +1 -OR- Constitution: +1
You must select which ability score bonus at the
time of attunement.
This magical ring protects against being
Charmed. Any time you fail on a saving throw
against being charmed, the chain links on this
ring begin to glow brightly. Reroll the saving
throw. On a success, roll a d4. On a 1, the ring
shatters and you suffer 1d6 fire damage.
Requires Attunement.