Synch Blade

Synch Blade (シンクロブレード, Shinkuro Burēdo^?, lit. "Synchro Blade") is an ability that appears in Kingdom Hearts II. It allows the user to summon a second Keyblade during battle. So far, the only characters to use this are Roxas, who can use this ability to wield his twin Keyblades Oathkeeper & Oblivion, and Sora while in Valor Form, Master Form, and Final Form as well as Double Form.

Story

Kingdom Hearts II

Roxas can use two Keyblades at once because he has both Sora and Ventus's Keyblades, due to Ventus's heart remaining within him. Originally, he just wields Sora's Keyblade, as Xion's creation had siphoned away Ventus's Keyblade. However, when she is defeated, his powers return to him, and he reawakens the ability to use Ventus's Keyblade.^[1] After Sora and Roxas reunite, Sora is able to use Synch Blade within Valor, Master, and Final Form, but since Sora possesses every ability that Roxas had,^[2][?] it is theoretically possible for Sora to use Synch Blade naturally, without going into a Drive Form.[citation needed]

Mechanics

In Kingdom Hearts II, Synch Blade is a support ability. It grants the user access to the abilities of both of their weapons.

An interesting note is in Kingdom Hearts II, Roxas dual-wields with Oathkeeper and Oblivion, both of whose abilities are related to Drive Forms, which is needed for Sora to access Synch Blade.

Learning Synch Blade

Kingdom Hearts II and Kingdom Hearts II Final Mix

Roxas learns Synch Blade immediately before fighting Axel in the Basement Hall. The ability cannot be used after the fight ends.[citation needed]
Valor Form has Synch Blade as a default ability.
Master Form has Synch Blade as a default ability.
Final Form has Synch Blade as a default ability.

Other appearances

Kingdom Hearts 358/2 Days

While Synch Blade is not an ability outright, Roxas can dual-wield Oathkeeper & Oblivion in Story Mode on Day 358, and in Mission Mode by equipping Zero Gear with three Ability Units.

Kingdom Hearts III

While Synch Blade is not an ability outright, Double Form allows Sora to wield two Keyblades. Roxas also continues to wield Oathkeeper & Oblivion as a party member in the Keyblade Graveyard.

Kingdom Hearts III Re Mind

While Synch Blade is not an ability outright, Roxas wields Oathkeeper & Oblivion as both a party member and a playable character in the Keyblade Graveyard.

Notes and references

^ Kingdom Hearts Birth by Sleep Ultimania, p. 617; Interviewer: "Why can Roxas dual-wield?" / Tetsuya Nomura: "Sora can wield two Keyblades at once because he has Ventus's as well as his own. As Roxas is a part of Sora, he also can use two. In Days, Roxas awakened his ability to dual wield after fighting Xion. In KHII, once Sora absorbs him, he can also dual-wield." Translation via Lissar.
^ Kingdom Hearts II: "All of Roxas's abilities and munny have been passed on to Sora."

[1] Kingdom Hearts Birth by Sleep Ultimania, p. 617; Interviewer: "Why can Roxas dual-wield?" / Tetsuya Nomura: "Sora can wield two Keyblades at once because he has Ventus's as well as his own. As Roxas is a part of Sora, he also can use two. In Days, Roxas awakened his ability to dual wield after fighting Xion. In KHII, once Sora absorbs him, he can also dual-wield." Translation via Lissar.

[2] Kingdom Hearts II: "All of Roxas's abilities and munny have been passed on to Sora."

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