Animated Snowman

Melting Snow. If the snowman takes fire damage, it starts to melt. Until the snowman moves at least 20 feet rolling around in a sufficient source of snow, or takes 10 or more cold damage, the snowman's speed drops to 0.

Snowball. Ranged Weapon Attack: +5 to hit, range 20/40 ft., one target. Hit: 7 (1d6 + 3) bludgeoning damage.

Frostbite. (your proficiency bonus uses/long rest) The snowman targets a creature it can see within 60 feet. The target must succeed on a DC 15 Constitution saving throw or take 1d10 cold damage and have their speed reduced by 20 feet until the start of their next turn. On a success, the target takes half damage and suffers no other effects.

Compaction. (2/long rest) If the snowman takes 10 or more cold damage, it can use its reaction to instead take gain immunity to cold damage from that source. If it does so, the snowman grows one size category for 1 minute. The snowman loses this immunity immediately after growing.