Dylan: "By Voldemort, I've only mastered the full-level Unforgivable Curses, please believe me, I'm really a good kid, just look at what I've done at school!"
Professor McGonagall: "Are you referring to, you using a hundred Dementor's Kiss spells per second to defeat an entire gathering of Death Eaters, and associating with a group of Dementors, being able to control them at will?"
Dylan: "No, I mean, there's not a single book in the library that I haven't read! All my courses are at full level, and so are my spells! Even Voldemort was defeated by me using the Unforgivable Curses."
Professor McGonagall: "Yes, exactly, and those cultists even want to elect you as the new Dark Lord!"
Dylan: "Good heavens, Professor, isn't this easy to solve? I'll just Avada Kedavra all those Death Eaters, and then no one will want me to be the Dark Lord!"
Why are the Unforgivable Curses always so lame? How about a max-level Lumos that shoots an instant laser beam? Or a maxed-out Scourgify that pressure-washes evil off the walls? Or even a top-tier Reducio that shrinks your enemies down to bug-size!