Well, he was until Beerus showed up.
-mission 100
-no items
-1 character only teams
Music: Looming Threat ~ Yu-Gi-Oh 5D's
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https://www.youtube.com/watch?v=kbpqr6LiUQY
When Zexion sends Sora into his book world he's basically changing the world the same way Xigbar does with his space warping powers where he changes the platform you fight him on. Hacking either of these characters outside their original boss arena's can cause strange things to happen throughout different Worlds in the game. So here's a video showing just some of the weird shit that occurs when that happens.
In this video Zexion brings back the thorns in the Hall of the Cornerstone, fights in the Gummi ship hangar and underneath the Black Pearl.
Music:
Aquatic Base ~ Level 2 (SONIC the Hedgehog 2006)
Spotted - Team Plasma (Pokemon Black and White 2)
Main Menu (Guilty Gear Judgment)
Serenity (DBZ Ultimate Tenkaichi)
The Out of the World (Guilty Gear Isuka)
Wild Soul (DBZ Budokai 3)
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https://www.youtube.com/watch?v=mdE7pkRGcZ8