Bone Dragon King

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Haunted Castle
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It's widely unknown that this boss existed before Castlevania III: Dracula's Curse due to Haunted Castle's obscurity. There's nothing really special about how it attacks; it just rebounds around the area, trying to swarm you with its spikey bones. If you let it live long enough, it'll begin spewing 3-directional fireballs. The level of difficulty rises or falls depending on the weapon you possess at the time.

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Castlevania III: Dracula's Curse
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This skeledragon king, too, is always on the move--this time, it glides in circlular motions that force you to make timely ducks and jumps within the inadequately-platformed area. As you strike its head, parts of its spikey spine will break off. When it takes enough damage, it'll flee upward, cracking a barrier that'll cause a major flood that you'll have to endure while giving chase. When you finally catch up, you'll have to finish the job in the same way you started--and that water level will be rising, so you'll have to make quick work of it.

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Castlevania II: Belmont's Revenge
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This version of the king has such length that you'll never be all to see all of it at one time (except above, thanks to editing). The narrow passage within which the battle occurs has large entryways within its ceiling and floor, and the king will spend the encounter continuously entering one entryway and then almost immediately exiting another on the opposite plane. With the screen scrolling to the right during the battle's duration, you'll be forced forward, often left guessing as to the king's next exit point; you'll be given a small window of advance notice--that is, the trembling of an entryway. It's your job to in any event position yourself in a way that you can strike its head during the short amount of time it's present and in the best-case scenario score multiple hits.

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Castlevania: Bloodlines
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Fortunately, you have the advantage this time--the king is chained to the wall on the right. That doesn't stop it from viciously waving backward and forward to reach you from far across the room, though. It also holds the power to spew a purple flame from its jaws, and it'll combine this with its wavy movements to add unpredictability to its attack. Ordinarily, this would be an overwhelming task, but a safe spot in the room's leftmost corner will make things a lot easier.

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Castlevania: The Arcade
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The "White Dragon," as its known here, accosts the hero in a narrow hallway, breaking its way through the ground and roaring in anger. Though it remains stationary, the White Dragon breathes fireballs that spew the length of the hallway, giving the hero no quarter. If you get too close, the dragon will flail its head and attempt to knock you back. The main challenge is deflecting its fireballs while moving into a desired attack position, which shouldn't be too much trouble for those quick on the draw.

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Castlevania: The Adventure Rebirth
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This form of the Bone Dragon King is a more-advanced version of its Bloodlines incarnation, the main target, as always, its head. The initially-wall-mounted King slowly flails itself about, stopping to spew in succession four large blue fireballs, each with a limited homing ability; it'll then slam itself into the ground directly below, squashing the hero if his previous dodging landed him on the room's right side. The King will then become detached and flee off-screen, seconds later reemerging to put its large frame to use by encircling the chamber's floor--which leaves open a limited number of safety spots--before exiting stage left. Its individual bones will then gather back at the right wall, from which the creature spawned, and reform, restarting the cycle.

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