Yu☆Gi☆Oh!: Sevens

 The seventh anime series in the Yu-Gi-Oh! franchise.

The series takes place in the futuristic town of Gouha and stars Yuga Oudou, a fifth-grade, elementary school student, who loves both inventions and dueling. Feeling that the current rules of the Duel Monsters card game are too stifling, Yuuga successfully manages to install a new set of rules of his own creation known as "Rush Duel", allowing for more fast-paced and frantic dueling. The series follows Yuuga and his friends as they show off the delights of Rush Duels while under the watchful eye of the Gouha Corporation that oversees the city.

(Source: Wikipedia)