Ice Cows are the gender swapped version of Ice Bulls. They guard the Ice Queen's castle and chase intruders. An Ice Cow chases Fionna and Nectr in What Is Life? into a door causing her to shatter and spill her organs. They may be summoned by the Ice Toad's alarm.
Ice Cows are bovine creatures made of ice. While Ice Bulls have four horns, Ice Cows have two horns. They have visible organs including an udder.