I think It was missing one more thing
*Trait: "CantFreeze"

I was going to apply the immunity to snow to Maid Fairy (Touhou Little Maid), but it lacks the trait on how mobs cannot freeze. E.g.: Snow Golem, Polar Bear, Stray, Iceologer (Friends and Foes), Maid Fairy (Touhou Little Maid 1.13), Yeti (Twilight Forest)

Implemented as of 25efac2.