Frost King doesn't spawn by itself, and must instead be summoned with a Frost Crown. He can be summoned at night in the Snow or Glacier biome.
Behavior
The Frost King will attempt to chase down the player and sit atop them. He has several attacks to hinder the player to allow him to close the distance.
Attacks
The Frost King has four different attacks. Each is telegraphed by the motions of his hands.
For his first attack, Frost King launches a large square of icicles outwards from himself. He communicates this to the player by raising his right hand.
The Frost King's second attack is Similar to The Ice Queen's ice pulse, launching a crescent at the player that can apply the Chilled Debuff. The Frost King telegraphs this attack by raising his left hand.
Expert Mode
Frost King doesn't receive any AI changes in Expert Mode, but he does get his own Treasure Bag.
Trivia
The name "Frost King" is a reference to the game Castle Crashers.
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