While usually happy thoughts were relegated to a very small file in his brain, Dementors were not repulsed by anything else. Thus, Calvary Golgotha, known to his associates as Cal, held his feeble Patronus Charm, a formless cloud, until Clarisse could be awakened. Out of the three of them, Clarisse had the most powerful Charms ability, and her Patronus, a penguin, had been known to swim through hordes of these soul-sucking bastards.
Tyfa was attending to Clarisse, but it was taking too long for Cal's peace of mind. Of course, being strangled until unconsciousness by a mummy wasn't the kind of thing to just pop back up from, even with magic. Too fast, and you ruin the voice, too slow, and they were going to be worse than dead.
Dementor after Dementor battered themselves against the wavering wall that was Cal's spell. He could feel their coldness starting to close around them like a careful hand. Unfortunately, this hand would strangle them in despair and then they would be free to close in.
Clarisse stood up behind him, swaying slightly from the effort. He doubted what kind of state her magic was in, but yelled at her anyway over the sound of dementors smashing his charm down. "Clarisse, Patronus, now!"
"EXPECTO PATRONUM!" Her voice was hoarse, but strong. Her Patronus fully manifested, the large, imperial figure of a silver Emperor Penguin. Moving as if the air had turned to water, the penguin Patronus glided effortlessly, repulsing and attacking the now-fleeing Dementors. In case they hadn't quite got the message, the Patronus opened its mouth and let out a wave of cloudy energy until it dissipated. The wave went through the air like ripples in a pond, scattering away every last trace of the Dementors for miles around.
Now looking less formidable, the forest was quiet. They had left behind the tomb and all of its terrors. Checking behind him, Cal saw Tyfa slip the Ancestral Amulet from around her neck into the travel bag she wore. For the first time, Cal smiled. Clarisse smiled too, in spite of herself and Tyfa let all the stress go and laughed.
The battle may have just begun, but for now, the victory was theirs.