I typed in "thunder plains concept art" on google and this image showed up:
FFX-2_Thunder_Plains_Concert.jpg
It's kind of creepy, isn't it? I can't decide who the bad guy is. Either the poor Gullwings are being surrounded by a horde of zombies, or a bunch of innocent people are being attacked by a giant crab which instills fear like Cthulhu.
Interestingly the picture was titled as "X-2 thunder plains concert". I wonder why Yuna is singing on top of the airship in such a place. She better have that black mage dress sphere ready or something
Feel free to make up a story for this picture or post your own picture for interpretation!