By his 3rd year Harry was tired of the magical world, and started to study the muggle world again. His greatest discovery was realizing how he could cause devastating muggle chemical reactions just by transfiguring things around him, even the air itself.
Voldemort stood amod the devastation of tue ministry, most of his death eaters criticslly injured, or dead. Himself burned and "So.. even Potter turns to dark magic, what would Dumbledore say to see you now?"
"Dark magic? No, i just realized how useful science really is in a world where no one understands it. Like this" Harry gave a small twist of his wand, then cast a simple spark, spell over Lucius. The already burned man screamed as his eyes erupted with a flash of fire over them. "Oxyhydrogen is an amazing thing to conjure."
Harry gave the dark lord a chilling smile "hey Tom, what happens when you throw water on a bunch of sodium?" As he pointed his wand at the transfigurrd floor Voldemort stood on. "auguamenti."