The Frost Giant is a giant hostile creature that is afraid of fire. They will follow you if you wear a Viking Helmet. Frost giants are vulnerable to heat, such as a fire, the Sun, lava spout, etc. He will be killed if put in an oven.
One of the Frost Giant's synonyms, Ymir, comes from the character from Norse mythology, father of the race of frost giants. The other two, Bolthor and Bolthorn, come from another Norse mythological character, grandfather of Odin.