If you ask a question and the question is a bad one for whatever reason, and upon learning this edit it to the point that it's not even the same question anymore, is that ok?
This question is what sparked my interest.
If a question is put On Hold, then it is almost certainly OK; part of the reason questions are put On Hold instead of Closed these days is to give the people who wrote them an opportunity to rewrite them so as to be useful, even if the edits are a bit drastic. But the question you linked doesn't seem to have ever been put On Hold, according to the revision history.
If the question already has good answers, and the editing might serve to make those answers invalid, then the edit might well need reverting. These are commonly called "Chameleon Questions", and Meta Stack Overflow already has a number of discussions on that topic. The short answer is generally "If it's mostly the same question, but a bit broader or a bit more in-depth, it's probably OK, otherwise play it by ear". But the question you linked doesn't seem to have had an answer at the time it was edited (or else any answers have been deleted, and I thus can't see them).
In fact, the post in question hasn't been edited terribly radically. It was originally about the maximum amount of damage that could be dealt by a specific ability ("how much damage would you deal with Lucian's ultimate?"), but now instead it asks for the build needed to maximize damage with that ability ("What would you have to build to get the most damage out of The Culling?"). All the edit did was preclude the near-infinite list of debuffs, items, etc. that other players could have that might affect the damage dealt, limiting the question to something that can be answered. By limiting the question to items, buffs, etc. that Lucian can get himself, the question became answerable.
Well, technically the question changed. Before, it was looking for the number, and didn't actually ask how, so an answer of "10324" or the like would have been horrible, but technically correct, whereas now it asks for a build, but not the number. This is extremely pedantic. Oh, and it technically no longer asks specifically about hitting a Champion. Not a big change.