u/Downtown_Year3636

When Free battled Dark Aiga with his evil resonance, Free destroyed him 5-0. This dark resonance is what Aiga used to first defeat Phi, and destroy Valt. Aiga had been beating everyone else in the show with his dark resonance. Even Dark Aiga was not powerful enough to defeat Free. Free was more powerful than his dark resonance. And he did this with no plot armor. Free is also the only character Aiga faced but never defeated in turbo. All of this is a point proving how Free is the strongest blader.

I honestly think Delta would've won, because at this point, Delta was shown to be very powerful and skilled, having never lost to anyone, or to Drum. And during this time they had us think that Delta was way stronger than Drum, and that same Drum got a burst finish off of Aiga (even though he wasn't going all out that round) But even when Aiga did go all out, he barely beat Drum because Dragon landed outside the stadium a second before Achilles. Also Aiga and Delta's first battle ended up a tie when Delta used venom diabolos, and in the next match he had erase diabolos. (his preferred, better version).

He may have even had his sights set on Valt after defeating Aiga, even though he wasn't champion during that time.