Yu-Gi-Oh, the tenth generation of card-playing simulator!

Yujo Judai's diary:
On August 2012, 8, I traveled to a strange world. The people here had very high dueling skills and a bunch of summoning methods that I had never seen before. I couldn't beat any of them, but fortunately I returned to my own world safely in the end.
August 2012, 8, great! The written test results are out. Because of that time travel, I was able to answer a question that I had never been able to answer before, and I got a good score of 12th in the written test! But why do I miss the duelists in that world?
On August 2012, 8, I traveled to that world again. Damn it, why can't I beat them?
......
On March 2013, 3, the principal said that there is a terrorist organization called Seven Stars in our world?
On April 2013, 4, the seven stars were all solved, and they were delicious.
.......
Hey, it’s the gate to the new world! ?