[Tusjecht]

Maybe that's the balance for being so strong, he's only good in a specific field. Just maybe.

You've covered tag duels, which I agree on.

As for why he didn't abuse his power, i can only comment that of all the red avatars, they seem (at least) to have some of the best 'bros and pals' characters as controllers. Usually, if they're seeking friends and bonds...I imagine they wouldn't want to jeopardise that. Just a thought, I can't really back it up.

Why did Merrow and Lagoon not see it? Well, chances are, he simply went to the field to grind at night, remember 'day outside, three years inside.' And he would have to grind, he can't keep giving Merrow and Lagoon an unlimited supply of points without losing his BB.

And after they got to level 4 and could go to UNF, he ground less often to avoid showing his full power, and when hunting with them, let them shoulder most of the burden to train their duelling skills.