First, the question remains: Why would anybody cast the apocalypse spell (Dumbledore mentioned omnicidal maniac Dark Lords, though).
Second, I still don't think the True Patronus is all that powerful. It cannot be used offensively against anything other than dementors and it does not defend against any magical, technological, natural, or creative-use-of-magical (such as the Mass Accelerating Charm) other than the killing curse, including ones that are just as fatal and which are probably almost as hard to shield against. Moreover, in noncombat uses the True Patronus gives almost nothing that cannot be given by the mundane Patronus or other mundane magical or mundane technological means. (the only thing I have thought of is an unforgable signal of anti-deathism to people able to understand the philosophy of the Patronus or the True Patronus.
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 87. The previous thread has passed 500 comments.
There is now 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.)
The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system. Also: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17.
Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically: