Ice Wraith

The Frost Wraith would be an undead mob, possibly of the zombie family. Being in a 7 block radius would give the player the frostbite effect, and it would freeze water like frostwalker. I imagine it would not be limited to ice biomes though. Depending on it being a zombie or a ghost it can drop scroll ask or rotten flesh, possibly both. It can possibly be the segway to add ice magic/enchantments into the game.