It bears repeating that there's always room for another good Attack on Titan mash-up. TeSh has an outstanding one, full of a nice narrative and great action as Madoka Magica's mahou shoujo face off against Walpurgis Night.
Also, the training corp performs the Nyarko-san W theme
And the rare case where Titan has been fit into another anime's opening, Angel Beats! specicially...
Bonus theme on violin
Attack in Minecraft
on Tawianese TV