Chrono's moment comes in the Jump arc when he uses the Jewel Seeds to create a Black Hole opening into the Sea of Chaos to defeat Mazoku Lord Death Bringer Garoth.
How about shortly after that when Reinforce gets a Big Damn Heroes moment, saving Lina from Death Bringer?
The Climax to the Try arc has not one, not two, but SEVEN Dragon Slave-level spells being used against the Big Bad before using Fusion Magic to defeat said Big Bad.
Suzuka, with no apparent magic abilities, punches a Mazoku General down a block and into a parked car, totally ruining the car and making the General comment that if she was a lesser demon, she would have been killed from that punch.
When Yuuno is attacked by a female Mazoku assassin, he snaps off not only some innuendo, but he also pulls out an attack that would make Simon proud of him.
In the strikerS!Arc, Teana, with the help of Sein, manages to completely destroy not one, but two Megahs with a supped up Starlight Breaker. She then gives Sein a piece of her mind of the torment that Teana's suffered from the cyborg over the course of the arc, before finally kissing her and telling her that she was under arrest.
When Quattro summoned Megahs around the Riot Force building, Suzuka beat the living daylights out of a Megah with her non-magical fists, dodged a bunch of lasers, and then tossed it into a group of the things. Signum's epic return for Arisa and the Florian sisters reunited and then wiped out a few of them, ignoring the Anti-Magic field.
Levi vs Kuma at his full magic potential. That is all.