Xros Heart heads for the Great Bagra Palace to rescue Yuu and reclaim the Code Crown, which Bagramon and DarkKnightmon have transformed to the Dark Stone. When they arrive, Bagramon proceeds with his plan to activate D5, the Day of Ultimate Destruction, which will destroy all dimensions and fuse the Digital and human worlds into one. As the destruction unfolds, Taiki and Mervamon fall through the collapsing ground and vanish! What will come of Taiki, and of the Digimon and human worlds?!

As Bagramon proceeds with the Day of Ultimate Destruction, Taiki and Mervamon find themselves trapped under the Great Bagra Palace. There they discover Yuu, but a new enemy stands in their way when they attempt to save him. Meanwhile Kiriha watches as DarkKnightmon forcibly fuses with Bagramon, creating an immensely powerful DigiXros that destroys whole realms and all the data in them. Is it too late for Taiki's team to stop D5?!

Taiki gets his own soul sent to Prison Land to bring back the souls of Shoutmon, Dorulumon, and Ballistamon. Soon he finds himself under the attack of the souls of the seven Death Generals, who overwhelm Taiki's Digimon in power. Taiki is in a tight spot... when Olegmon realizes that the Death Generals are not his true friends and, along with the just Apollomon, joins Taiki's side! Does Taiki stand a chance against the other five Death Generals with their help?!

Beelzebumon's sacrifice has allowed everyone to escape Hell's Field and return to Bright Land. But Apollomon Whispered has also returned, and is preparing to wipe out all of the Kingdom's Digimon. When Taiki pursues him, Whispered assumes the form of Apollomon to weaken Taiki's resolve to fight. Has Whispered won, or can Taiki find the strength and courage to fight his friend?!

After defeating all seven Death Generals, Taiki and his friends reach the Great Bagra Palace. If they can defeat the Emperor Bagramon there, the Digital World will be reborn, and they can resurrect their fallen companions. But instead they're greeted by DarkKnightmon, who uses the power of the Dark Stone to resurrect all the Death Generals. With their souls taken away, they attack Taiki's team like robots... until DarkKnightmon forces all seven of them to DigiXros into the ultimate god of destruction!

Yuu has run away after learning that there is no world without pain and suffering. As Taiki's team tries to find him and get everyone out of Hell's Field, Apollomon Whispered merges Lilithmon and Blastmon into a monstrous new Lilithmon bent on revenge! Meanwhile, Wisemon devises a false program to let everyone escape Hell's Field without forcing Taiki or Yuu to die. But Shoutmon X7 must protect the castles while the program is activated, leaving him unable to fight. So the injured Beelzebumon sets off to stop Lilithmon himself...

Yuu has thrown Taiki and his friends into a dark realm called Hell's Field. Inside a castle they find a crystal that allows them to speak with Yuu, who tells them that his army has taken up camp in a castle opposite the one that Xros Heart has found. He then invites Taiki to play a game in which they each lead their armies against the opposing castle, and whichever one dies is the loser. Yuu still believes the Digital World is a game in which nobody really dies, so Kiriha comes up with a strategy to convince him that he's wrong. Will Kiriha's strategy succeed in showing Yuu the truth?!

The big showdown between Taiki and Yuu has begun in Hell's Field. Yuu attacks with a sword, overwhelming Taiki with his surprising strength. As they battle, Yuu confesses his reason for hiding his true strength all along, and reveals the words of DarkKnightmon that freed him when he came to the Digital World. Finally Taiki sees Yuu's true nature and vows to fight him in earnest. Can Taiki defeat Yuu and make him see the truth?!

Taiki's team arrives in the seventh and final Kingdom, Bright Land, where the Death General Apollomon asks them to help him defeat Bagramon. Just when Kiriha and Nene are convinced to trust him as Taiki does, Yuu and Tuwarmon appear and activate a dark program called Whispered, which Bagramon had embedded in Apollomon. To defeat Whispered means to defeat Apollomon... Can Taiki find the resolve to fight their new friend?!

Taiki, Nene, and Kiriha are once again bound tightly by their strong friendship, giving rise to Shoutmon X7! With his ultimate attack, Shoutmon X7 at last defeats Gravimon... but he is reborn again thanks to a "heart" hidden somewhere in his castle. As long as his heart survives, Gravimon can come back to life infinitely. So Nene slips into the castle to destroy the heart while Taiki and Kiriha engage Gravimon in battle to draw him away from her search. Taiki attacks with a new seven-way Xros based upon Cutemon... but can they hold Gravimon off long enough for Nene to find his heart?!

Instigated by the Death General of Canyon Land, Gravimon, Kiriha resolves to defeat Taiki in order to obtain ultimate strength. Taiki is forced to fight back, sending OmegaShoutmon against Kiriha's ZekeGreymon. However, both Digivolutions wear off before a winner is decided. Kiriha sends his guardian deity, Deckerdramon, to finish off Shoutmon, but Deckerdramon defies his order and attempts to remind him of the importance of love...

Taiki's party arrives in the sixth Kingdom, Canyon Land, where the Death General Gravimon commands a massive army. Kiriha takes charge as the team plans their battle strategy, and the others follow his lead... but Gravimon sees through their surprise attack and backs them into a corner. He perceives that something in Kiriha's past drives his desire to be the strongest, and tells him that he can do so by defeating Taiki himself. How will Kiriha respond to Gravimon's temptation?

Taiki and his team have been attacked by Dorulumon, who turns out to be the Death General Splashmon in disguise. A rift begins to form between Taiki and his friends as Splashmon continues to trick them one by one with his disguises. Cutemon and Revolmon find where the real Dorulumon is imprisoned and save him, but how can Xros Heart fight back against the powerful Splashmon?!

The Death General Olegmon's crew has turned Ballistamon into the ultimate destructive weapon, DarkVolumon! Olegmon uses him to attack and capture Taiki, whom he again invites to join his army. But when Taiki refuses, Olegmon orders DarkVolumon to attack Nene! Kiriha and Shoutmon soon arrive to save them, and Shoutmon attempts to restore DarkVolumon to his old self by calling out to Ballistamon through a DigiXros. Will his voice reach Ballistamon?!

Taiki and his friends land in the golden sea of Gold Land, where they encounter the Death General Olegmon, riding on a pirate ship. Olegmon has heard of their battles with the previous Death Generals and invites them to join his crew, but Taiki refuses and the battle begins. However, Olegmon begins to chant a strange incantation, and nearly all of Xros Heart's Digimon hear it and join Olegmon's army! Ballistamon, who was unaffected by the incantation, rescues Shoutmon from the enemy's grasp. They set out to defeat Olegmon together, but then an unexpected change happens in Ballistamon...

Mervamon's brother, Ignitemon, returns to the side of justice and joins Taiki's team in the fight against Zamielmon. He reveals to Taiki that the secret to Zamielmon's small, elusive size is DigiHoney, the power he steals from other Digimon. They then receive an invitation from Zamielmon to a theme park called Honey Park, and though they know it's a trap, they go there with a plan to make Zamielmon bigger so they can fight him. However, Zamielmon grows much bigger than Taiki expected, and Xros Heart must send Shoutmon DX to face his giant new form!