What Harry Potter Duels take place in Harry Potter and the Deathly Hallows?

In honor of The final movie coming out, me and my friend are dressing up and dueling while we wait for it to start. He is dressing up as a death eater and and I am dressing as an OOTP/Student. I need to know if there is a specific fight where a female member of OOTP or a student beats/fights a death eater. Please help, Thanks :)