Dumbledore thought the power referenced in the prophecy was love.
He was wrong.
Harry Potter stood in the middle of a destroyed Muggle city. Burnt husks of buildings smoldered gently, roads were cracked and covered with soot. His wand was trained on Voldemort, who stood across from him, roughly twenty paces away, with his wand also pointed at Harry. The battle had been furious, but it was brought to a standstill by the meeting of two titans, one of the light and one of the dark. Casualties were heavy. Behind Harry stood Ron, Hermione, Luna, Ginny, and Neville, the Ministry Six united in their last stand. Behind Voldemort stood rows of Death Eaters, each sneering at the diminished light warriors.
"You think you can defeat me, Harry Potter?" Vodemort yelled, his voice echoing across the silent clearing.
"Dumbledore always said that the power you knew not was love," replied Harry, confident. "I will defeat you."
"Love?" Voldemort cackled. "LOVE?! How is love supposed to defeat the greatest Dark Lord of all time?"
The Death Eaters jeered, smirking at the loss of the light.
"I-" Harry cut himself off, then sniffed. "GET AWAY!"
The teenagers surrounding Harry took their cues from him and Apparated far away, disappearing almost right after him.
"See?" yelled Voldemort. "Potter flees before my might. The Wizarding World is ours! We have-"
Then Voldemort and his Death Eaters blew up in an explosion of flames and asphalt.
From a safe distance, the light watched the dark forces burn.
"Harry!" shouted Hermione. "How did you make that massive ball of fire? You were exhausted!"
"I figured out the power the Dark Lord knew not, Hermione," he replied.
"What is it? Tell us!"
"Noses," Harry replied with certainty. "I smelled a gas leak."