Starting with OP's cool Red Texas' cool 'bait & switch' talent, there's some impressive examples of fish intelligence here.
Of course there are different types of intelligent behaviors in fish; most I see are food, survivor or escape motivated, all natural tendencies among fish but some take it to another level, as with Caligula.
However, when it comes to creative intelligence and doing something for simple pleasure instead of survival, I think my ~2 yr. old Kamfa Flowerhorn is pretty hard to beat, which I've posted about in another thread with video,
https://www.monsterfishkeepers.com/forums/threads/fish-can-be-artists.712708/
I'll admit to being a doting dad but imo he demonstrates a quite amazing sense of alignment, geometry and design that I've never seen to this level in another fish (though there could be examples I haven't come across) -- it's clear he has a plan in his head for each design and then executes it. When it's done he might make an adjustment or two afterwards (if I don't destroy it), but mostly he leaves them alone, he's content with his work and not doing it out of boredom (if it were boredom he'd keep re-designing his designs, which he never does until I re-pile the rocks).
Imho Flowerhorn and Red Texas are pretty much the overall smartest aquarium fish (fire away
)