Xigbar is a boss in both Kingdom Hearts II at The World That Never Was, and Kingdom Hearts 358/2 Days at Olympus Coliseum. He returns in Kingdom Hearts III as one of the bosses of the Keyblade Graveyard, fought alongside Dark Riku against Sora and Riku
Kingdom Hearts II
Xigbar begins the battle by warping to a ledge overlooking the arena Sora is on, and an HUD display appears. Xigbar fires combos of laser arrows at Sora just after the circles and rotating dots on the HUD align. Use the Reaction Command "Warp Snipe" to deflect Xigbar's shots. Once Sora has deflected three shots in a row, Xigbar teleports back to the ground. He may repeat this attack at least once more in the battle.
For most of the battle, Xigbar rapidly teleports around the arena, firing combos of laser arrows at Sora. These arrows can be dodged, or reflected back at Xigbar with Guard for minor damage. After approximately three combos, Xigbar temporarily stops attacking to reload his Arrowguns. At this time, Sora can easily strike him with a combo. Xigbar hovers upside-down throughout the battle, so Sora must jump to reach him. To grant Sora maximum mobility in this fight, make use of abilities that grant aerial combos. Leveling up Master Form to acquire the Aerial Dodge ability not only allows Sora to deflect Xigbar's bullets back at him with proper timing, but also gives Sora more time to strike Xigbar with aerial combos.
Throughout the battle, Xigbar frequently shifts the shape of the arena. In one shift, Xigbar narrows the arena, firing at Sora rapidly from the opposite end. In the second, Xigbar converts the arena into a narrow box-shaped path, with a single platform extending into the middle of the arena, over which Xigbar hovers. In the third, Xigbar creates a box-shaped arena with an intersection of platforms meeting in the middle. Xigbar combos to bombards Sora with laser arrows; Sora must strike him with a finishing move to shift the arena back.
Later in the fight, Xigbar charges large, blue laser arrows, several of which ricochet around the arena. These arrows bounce in addition to Xigbar's normal Arrowgun attacks and teleportation. Sora can use the Reaction Command "Warp Snipe" to deflect up to three of these blue arrows at Xigbar to damage him. Xigbar also begins firing multiple shots in quick succession.
When low on HP, Xigbar adds a new attack to his repertoire. He shifts the arena again into a small, square platform, and fires a barrage of laser arrows while rotating in a circle. He then teleports into the space around the platform to unleash several more attacks. Finally, he teleports into the air above the platform and fires countless laser arrows above him. This can be avoided by jumping to the far left corner of the platform, then running counter-clockwise, behind Xigbar's shots. The final phase of this attack can be avoided fairly easily, as Sora's movement speed is just fast enough to outrun Xigbar's shots. This is easily Xigbar's most dangerous attack, capable of stunning Sora until the attack is over, rendering him unable to heal while stunned. Alternately, Limits can be used to avoid it.
Xigbar's normal attacks can be blocked with Guard, Reflect or Warp Snipe. Due to Xigbar's constantly teleporting and shifting the face of the arena, getting close enough to do damage can be difficult. Make good use of Sora's various abilities to stay mobile while evading or deflecting Xigbar's long-range attacks.
In the data rematch, Xigbar begins by transforming the stage. Xigbar no longer needs to reload his weapons, so the only way to approach him is to deflect his shots back at him using Guard or Reflect, which stuns him for a brief period. His shots now move much faster as well. When he leaves the area to snipe, he can now shoot rapid-fire at Sora before the "Warp Snipe" Reaction Command is available. His charged blue shot now takes almost no time to charge and becomes far too quick to reliably use the Reaction Command, so it is better to cast Reflect before it hits to dissipate it.
Kingdom Hearts 358/2 Days
Xigbar challenges Roxas as the other finalist in the Olympus Coliseum's games. This battle is not a fight to the finish, but immediately ends once Xigbar's health is lowered enough.
Xigbar occasionally leaps back and fires two shots at Roxas from the air. Xigbar only performs this attack twice in a row. If Roxas travels out of his range, he teleports to a nearby location. Xigbar can only fire sixteen shots before running out of ammo; so exploit the chance to get closer to deal some damage while Xigbar stops to Reload. Dodge Roll, and Glide allows Roxas to dodge his shots while staying mobile. The bullets can also be blocked.
Kingdom Hearts III
Xigbar serves as one of the bosses of the Keyblade Graveyard, fought alongside Dark Riku against Sora and Riku. The battle against him is highly reminiscent of the boss fight in Kingdom Hearts II. It is recommended to defeat Xigbar first as his long-ranged attacks make fighting Dark Riku difficult. Xigbar mainly hovers upside-down in midair, out of reach from Sora and Riku, and attacks by firing homing arrows from his guns and firing a spread shot of arrows after charging up energy. Any arrows that don't hit Sora will linger on the ground, acting as mines that will explode and damage Sora if he makes contact with him.
After performing several attacks in a row, Xigbar will stop to reload his arrowguns, leaving him vulnerable to attack. All of Xigbar's attacks can be easily avoided, or more preferably, reflected back at him with Guard to deal damage. The Countershield and Frying Pan formchanges are essential in this regard as Xigbar's shots can be used to gather energy for their respective Wrathful Flurry and Flame Barrage reprisals. For players who wish to fight at a distance, the Double Arrowguns, Magic Launcher, Hunny Blasters, and Hunny Launcher Formchanges are ideal choices (though the Hunny Blasters and Hunny Launcher are better options as Guardian Form's Barrier ability makes it easier to reflect Xigbar's shots). The airstep maneuver is also a great way to close the distance between Sora and Xigbar while avoiding his attacks.
After enough damage, Xigbar will begin glowing with dark energy and begin his desperation attack. The Freeshooter will teleport to the center of the room and combine his arrowguns into a large bow. He will then fire an energy arrow into the air, opening a spatial rift that rains down countless arrows of dark energy which will slowly expand outward to the edge of the room. Despite the attack's wide reach, it can easily be avoided with either a well-timed Dodge Roll, airstepping towards Xigbar, or by guarding against the arrows. So long as Sora reflects Xigbar's shots, makes good use of the airstep maneuver, and routinely heals himself and Riku, Xigbar will fall with ease.
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