Ring of Warmth

Ring, very rare (requires attunement)

The ring’s warmth flows through you, granting you resistance to cold damage, and whenever you take cold damage, you heal gain 5 temporary hit points. All adjacent creatures to you of your choice are also resistant to cold damage. You also do not take any ill effects from being in a cold environment. You can cast counterspell as a 3rd-level spell against any spell that deals cold damage. Once you have used this counterspell, you cannot cast it again until you complete a short or long rest.

Epic Attunement. You instead have immunity to cold damage and all creatures of your choice within 10 feet of you have resistance to cold damage, and do not take any ill effects from being in a cold environment. Finally, the counterspell that you can cast acts as if it were cast in a 5th-level spell slot.