No Heart is a boss exclusive to Kingdom Hearts Birth by Sleep Final Mix. He is a data simulation of Xehanort in his Keyblade Armor, and is fought within the "Peering into Darkness" battle in the Mirage Arena. He wields the No Name in battle. At the beginning of the battle, he sits on a throne in the Throne Room of the Land of Departure, and he later stands up to fight the character directly.
No Heart is one of the strongest secret bosses in the game, rivaled only by Young Xehanort. His attacks are strong and can deal heavy damage. In terms of preparation, the character should be at a high level, have a strong Keyblade, max HP, and lots of Cure and Potion commands, as well as have the Second Chance and Once More abilities equipped.
In the first phase of the battle, No Heart remains stationary, protected by a large barrier of dark energy. To disable the barrier, the character must attack No Heart's Keyblade, which is constantly floating around. In terms of offense, No Heart will summon a swarm of flying Keyblades from the Keyblade Graveyard that can be blocked, or even destroyed by commands such as Raging Storm, to attack the character and sometimes use an advanced Corridor of Darkness that absorbs and traps characters on the barrier ( must be pressed repeatedly to break free), and may use Dark Volley. No Heart's Keyblade is vulnerable to any attack. After dispelling the barrier, the fight becomes more serious as No Heart rises from the throne, removes his cape and challenges the character directly.
This is the harder phase of the battle. The boss possesses an arsenal of potent dark-based attacks which can deal large, and possibly fatal damage. No Heart mainly uses Sonic Impact, darting around the arena to attack the character. The boss can utilize Dark Volley to strike from a distance, as well as summon flying Keyblades to attack. The boss can create waves of dark energy by swinging his Keyblade. He may also leap into the air and slam the ground to create a large shockwave. No Heart can use Reversal to maneuver around the character to unleash more Keyblade strikes, and may completely block attacks with his Keyblade. No Heart also can create large pools of dark energy that will either slow down or speed up anything that is inside, and may even bind the characters in place with no means to move aside. The armor can also alter the shape of his Keyblade for strong attacks (a similar fighting style to the Lingering Will) such as turning it into a claw to grab characters ( must be pressed repeatedly to break his grip), a spinning duel edge blade, a gun that can shoot powerful shots, morphing it around his leg for powerful kicks, and turning it into a wing to fly. From the air, he will either shoot more dark energy blasts, summon more flying Keyblades to attack, dive at the hero repeatedly, or use his most powerful attack: A large explosion of dark energy that will instantly drain all HP, Commands, the focus gauge, and may leave the player character stunned if characters are in the vicinity. He may also telekinetically command his Keyblade to attack characters directly and to absorb any damage directed to him.
Heal Strike, Renewal Block or Barrier, and a Command Deck containing Thunder Surges alternating with Cure spells will lead to an easy victory. Once More and Second Chance should be equipped as well. Thunder Surge is particularly useful compared to other techniques because it can lead into the powerful Rhythm Mixer Command Style. Victory against No Heart depends on careful timing and conscientious healing.
In the HD 2.5 ReMIX version, like with Young Xehanort, the difficulty of No Heart's battle appears to have been toned down. While he is still as dangerous as in the original version due to his increased evasion and speed in the HD Remix, he is now vulnerable to Shotlock attacks like Aqua's Lightbloom, which take away a good portion of his health.
The reward for defeating No Heart is the Royal Radiance Keyblade.
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