The Epic of Alexander [Ultimate] unlock dialogue might be reference to...

[Jonnycbad]

Wandering Minstrel: Alexander, you say? A clockwork citadel that did rise from the Thaliak to loom boldly above the far reaches of snow-swept Dravania? Intriguing. Most intriguing, indeed...
Wandering Minstrel: ...Forgive me, friend. I just felt a flicker of recollection. A sense that I had come across a similar sight in my own travels of far-flung worlds. A mighty colossus of metal housed in the innermost chambers of a tower that shone with blinding light. But this is your story─do tell it"

Tower of Babil

Giant of Babil

[MrThinker]

Tower of Babil

Giant of Babil

You'll have to excuse the lack of reference, but I remember reading that FF4's Giant of Babil was originally meant to be named Alexander, but they changed their minds before then reusing the idea for his first appearance as a summon. So maybe that's why they are referencing it...

[Iscah]

Sounds more like he stumbled into the depths of the Twinning...

[MrThinker]

And now I remember that the giant wasn't actually within the tower