Possible spoilers for those who haven't yet done it, but
the Shantotto event clearly references the A Shantotto Ascension mini expansion in FFXI - not only did the FATE use the expansion's final battle theme Feast for the Ladies, Shantotto's comments in the cutscene at the end of the event specifically refer to her 'Shatottofication' spell to cross dimensions as used in that expansion (not to mention her eyes glow red briefly like the Shantotto clones in the expansion). And the quest beginning and ending title card uses the FFXI logo itself. :3
And fittingly she mentioned Windurst and Vana'diel as well, which I smiled at (as my character in FFXI is Windurstian), but naturally drew puzzled looks from the Gridanian NPCs she was speaking to.

I would have still liked to have actually had FFXI-themed gear instead of just a minion (like the Combat Caster's gear and the Fire Staff Shantotto uses) though, but ah well, this event was lots of fun anyway...
Thank you SE for this awesome crossover!