Ice Rat (5e Creature)
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Small beast, unaligned
Ice Walk. The rat can move across and climb icy surfaces without needing to make an ability check. Additionally, difficult terrain composed of ice or snow doesn't cost it extra moment.
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 4 (1d4 + 2) piercing damage.
Frost Breath (Recharge 6). The rat exhales a 15-foot cone of cold air. Each creature in that area must succeed on a DC 10 Dexterity saving throw, taking 5 (2d4) cold damage on a failed save, or half as much damage on a successful one.
Ice rats are cousins of giant rats that have adapted to live in freezing climates. They have white fur and piercing blue eyes. It is said that they have trace amounts of elemental ice in their blood.