Assuming there is a viable plan to disable all opposition Harry can just state this fact in parseltongue and buy time with that. The dark side of Harry surely can come up with one along the lines of partial transfiguration threads of say Iridium ("Beneath the moonlight glints a tiny fragment of silver"..."). Enough approaches that seem conceivable have already been posted.
Actually he has to state this before executing it because that reduces the risk of the intervention as required per the vow. On the other hand he cannot protect earth when dead so he actually has to choose fighting over dying.
Thus his first sentence migt be something like:
"I have a meansss to disssable all opposssition and cause your retreat or death. I mussst use it to protect the world if you do not reduce the risk of my death."
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 113.
There is a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)
IMPORTANT -- From the end of chapter 113: