Consider Bringing 'WorldEnd: What are you doing at the end of the world? Are you busy? Will you save us?' Into This Crossover or Adding References to It

     Consider also adding WorldEnd: What are you doing at the end of the world? Are you busy? Will you save us? into this crossover or at least including references/shout-outs to it. One idea for doing this is one I also just added into the post I made on the SpaceBattles forums as a new, second part of this section which I'll quote here:

You could also make a WorldEnd AU work with the Aincrad arc in an 'Aincrad's real' AU with extra floating islands — perhaps with some of the close-by ones playing host to my 'Alternate In-Game Aincrad Entry AU Idea' — perhaps/likely by having said WorldEnd AU's surface world below not be quite so post-apocalyptic as it is in canon.

Also, per this other SpaceBattles post I just made more recently:

Come to think of it, this'd potentially also work with that same LBX Girls AU/Girls' Frontline AU/Log Horizon AU idea from the 'Crazy Crossover Concepts: Round 5' post of mine I also linked just previously with this alternate SAO × WorldEnd crossover idea I just added to my multi-post from earlier.

(See also #31.)