by gsteemso » Sun Oct 09, 2016 12:56 pm
Admittedly of questionable relevance given that what you specifically sought has already been found, but one of Narsil's series (they can be found on AO3) has this in it (and a great deal else, of course). I believe either the first story or possibly the series as a whole was called "Things Change". Now, on other web fora I have seen people express extremely polarized opinions of this author's works, with some people generally liking his stuff (I am among these), and others considering it to be not merely "really bad," but actually "legendarily awful." Thus, approach with some caution, especially as the first chapter contains distressing material which is unfortunately necessary to set up the conditions under which the remaining plot can occur, but if you can handle a tonally very different take on the rather silly source material, the writing is mechanically excellent and the ideas well-executed for what they are.
My main peeve with this author is that his headcanon features the inexplicably fanon Timeline-Manipulating Crystal Tokyo Arranger Setsuna rather than the canonical Timeline-Preserving Gate Guardian Setsuna. As things go, it's relatively minor, and I feel that his stories' antagonists remaining contextually credible in spite of this inherently overpowered support character goes a good way to making up for it. YMMV.
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