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Ichigo meets a man named Ginjo who is part of a group called Xcution. He tells Ichigo that they are humans born with Hollow powers and that they want to get rid of their powers to be normal humans. Ginjo tells Ichigo that the only way they can forfeit their powers is by transferring them to someone who is opposite of them; someone who is a Human/Shinigami. Hence, Ginjo agrees to restore Ichigo's Shinigami powers.
Without going into too much detail, Ginjo helps Ichigo gain a new type of power called Fullbring. Not long after, Ginjo betrays Ichigo and steals his Fullbring powers to make himself stronger. While Ichigo is powerless again, on the floor crying and screaming at Ginjo to give his powers back so he can protect his friends again, someone stabs Ichigo through the chest from behind. He turns around and sees that Rukia stabbed him with a special sword invented by Urahara. All of the captains of the Gotei 13 transferred a portion of their reiatsu into this sword and it's enough to awaken Ichigo's buried Shinigami powers again.
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We find out that Ginjo was once a Substitute Shinigami Representative that went rogue. Ichigo is currently fighting him 1v1. Byakuya, Kenpachi, Hitsugaya, Ikkaku, and Rukia are also in 1v1 fights with the other members of Xcution.