Erm, nobody seems to have brought up the Killing Curse, am I missing something...? Like, that should be the HP verse's workhorse spell here, considering that it is hax that that bypasses all forms of personal projection should it actually hit; the only exceptions are very marginal, HP specific situations that don't really apply here (Sacrificial Protection, Priori Incantatem, Phoenixes via resurrective immortality, etc). It's also something that should be readily available to the HP combatants, because while the Killing Curse is difficult, it's not like, impossibly difficult or anything, you can learn it if you're a sufficiently skilled wizard. Hell, a lot of wizards should already know it- just learning Avada Kedavra isn't illegal, what's illegal is using it on a person, and there's plenty of precedent for the ban on the Unforgivables being lifted in wartime conditions.
The reason why I bring this up is that there's a lot of talk about how many biggaton effects that HP wizards can manage to pull off, which feels like it's completely jumping the gun, lmfao. Avada Kedavra is simple, readily applicable to personal combat, casting it shouldn't be significantly harder than a lot of the biggaton attacks/OP potions that are getting mentioned here, and it moots enemy durability. Like, look at this-
Are you sure
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