So outside of post game bosses and final bosses what was the hardest boss you’ve had to fight that just too wayyy to long to beat to the point it wasn’t fun anymore?

For example, In FFT:WoTL , the hardest thing I had to do was fight Belias the Gigas. My team set up was not the best for it and Ramza at the time was too under leveled and ill equipped. It took me about 12 tries to win and only did so ‘cause Agrias crit on the Gigas