Heck, the Ghoul School girls get a Crowning Moment of Awesome simply for being nice enough girls that Shaggy and Scooby are willing to hang around monsters for an entire school year without screaming their heads off.
Revolta is completely neutralized as a threat in two moves, and it's thanks to Tanis and Elsa. Tanis uses her bandages as a "lasso" to take Revolta's magic wand away from her and change Scooby back, and Elsa then throws the wand into the fire, destroying it.
Tanis:I want that wand!
Sibella was the only ghoul who almost got away from from the spiderbats, and she was strong enough to nearly manage to shake off the hypnosis—even Revolta notices it.
Scrappy managing to trick the Well Dweller into helping him, Scooby, Shaggy and Matches escape.
Not to mention earlier, when he and Matches built a catapult that helps them enter Revolta's Palace.
Let's not forget how he and Matches scared the Mirror Monster back into the mirror.
In the climax, Scooby (who has been turned into a toad by Revolta) successfully reversing Revolta's potion by knocking over different bottle and other items into the cauldron, thus freeing the remaining girls from Revolta's control.
In the same scene, Matches regains his ability to breathe fire and attacks Revolta's spiderbat who is chasing after Frog!Scooby. Not only is he able to fight back again, but he also saves Scooby who he has spent most of the movie antagonizing.
