Storm the Rainbow Dragon

Storm the Rainbow Dragon is one of the four dragon boss battles as well as being one of the final bosses fought in the game. He is first seen in a cutscene burning Fallstown and killing Lochran with his breath as well as kidnapping Madelyn and bringing her to his master: the Nightcaster. But he is not fought until the player ascends the top of the Island of Yew. Being the Rainbow Dragon, he can rotate between the four elements during the battle starting with Fire then rotating between Dark, Light, and Water before returning to Fire.

Trivia

 * This is one of two boss battles where no runes can be used, the other being the Nightcaster.
 * As a result, this is one of two boss battles along with Shadow where it is impossible to heal due to the Light Rune not being allowed in the battle.

Quotes

 * "Tsk. Tsk. Tsk... a pity, Old One. You have come so far only to fall within sight of your destination. How splendid!"
 * "You know that I cannot do that, Old One. Your journey ends here."