The Frost Elemental is an optional boss found in the Dark Palace of Waterfalls. She is a female entity clad in a harlequin-like attire covered with ice shards on her legs, hands, and other parts of her body. She has the power to control arctic chill.
Her main method of attack consists in creating ice blades around her right arm and lunging toward the player whilst swinging it.
Creates long, razor-sharp ice blades around both of her arms and starts spinning, launching herself toward the player and chasing them for a while.
Pulls back whilst surrounding herself with a purple aura and creates a long ice lance on her right arm, lunging and stabbing at the player.
Casts a freezing area-of-effect attack that causes Paralysis on contact.
Stops for a moment and conjures a potent ice beam that she keeps aiming toward the player for a short period of time.
The Frost Elemental is hidden near the beginning of the Dark Palace of Waterfalls. At the first intersection, take the left path (East), then again left/East at the second intersection. There is an Axe here and a silhouette of a door on the dead-end. Lure the Heavy Armor (spiked-ball knight) here and make him smash the wall to open a secret path. Behind is a cavern-like area where you can get a Super Potion, an HP Max Up (note that there's a "skull tunnel" in the HP Max Up room, which leads to the bottom level lever room, near the "Black Turtle" door) and the door to the Frost Elemental. It requires several well-adjusted jumps and whip-jumps. No items are required.