Conclusion

Three years have passed after the end of the Legion Mate arc. Chrono Shindou, an independent teenager, finds a Vanguard deck and a map in his school locker one day. After school, he follows the map to a card shop, Card Capital 2, where he sees his first cardfight between Mamoru Anjou and an older Kamui Katsuragi, who works part-time at the store.

Synopsis excerpt via Kitsu.