Your body transforms entirely into magical icy mist for the duration, granting you the following benefits:

• You are immune to cold damage and you have resistance to all damage except fire damage.
• You ignore the effects of disease, exhaustion, and poisons. Any poisons or diseases already in your system are suspended, not neutralized.
• You cannot be grappled or restrained.
• You can use a bonus action on each of your turns to release a breath of icy mist in a 30-foot cone which spreads around corners and extinguishes nonmagical flames, lasting until the start of your next turn. The area is heavily obscured and difficult terrain. Each creature standing on ground in the area when it appears, that moves onto ground in the area, or that ends its turn there must succeed on a Dexterity saving throw or fall prone.
• When another spell you cast deals cold damage, it ignores resistance to cold damage, and it deals extra cold damage equal to 10 + twice the spell's level. A spell can't deal this extra damage to any creature more than once per turn.