@ Kaoz: Fanbook 10.5
Speed - 10: Much is unknown about Byoudouin, but in his match against Oni upon entering the U-17 camp, they were hitting balls back and forth so fast that a violent dust cloud engulfed the entire tennis court. This suggests that his speed is top tier.
Power - 10: Byoudouin has an extremely powerful glowing shot that can break walls just because of the violent air around the ball as seen in page 9 of chapter 95. Oni returned the ball, but he still received a massive cut on his face and the wall behind him was destroyed.
Stamina - ?: Even if we were to assume there is room for growth in his stamina, When he was wandering the world going through special training and living the life of a hermit, he acquired a hardy and tough body. The manga has not given information about his stamina, but we can assume it is quite high as seen in his match against Oni.
Mental - ?: Having gone through special training up on top of the cliff, it seemed he acquired the interdimensional power and a spiritual nature. Already now, there are no weaknesses.
Technique - 10: Even though by his 1st year in high school he was nigh perfect, it is expected that after the world campaign, he has obtained something even greater. He has learned techniques from all over the world, allowing him to win in nearly any situation.
Kurobe Memo: Can there really be a high schooler that is already this high a level? There is nothing to criticize about his true abilities, but his manners are crude. We should teach him some more respectful manners so he doesn't embarass the title of being an All Japan Representative.
@ Korean Kuroku: I know but from what we know so far, who do you think?