Digimon Next!

Tsurugi Tatsuno is a boy who competes in Virtual Digimon Battle
tournaments. When a Kuwagamon appeared in the Real World, his Greymon
came to life and protected him. Tsurugi is summoned to the Digital
World by Piximon to save the Digital World from the evil Barbamon.
Since his Digimon has a hexagon shape on him, it's an Illegal Digimon,
meaning that Digimon bearing such symbols can help save the Digital
World. Tsurugi's Greymon later De-Digivolves to Agumon and they meet
other characters destined to save the Digital World from the forces of
Barbamon. Now they must stop Barbamon and his minions before they get
all the DigiMemories and take over both worlds.

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