You did not ask me to name anything? I was just giving an example of a challenging spinoff, which you mentioned a post earlier, and I didn't say numbered FFs are challenging.

But okay, here we go.

Final Fantasy II: no traditional leveling system, you really had to plan what to develop as opposite stats actually decreased

Final Fantasy III: limited phoenix downs, job proficiencies, and super beefed up enemies with multiple turns meant you had to plan every move and grinding took forever, so not only was it difficult to overpower the bosses, but even if you were overleveled, you could easily get wiped in a turn or two

Final Fantasy IV: the DS version especially, many bosses have lethal counters and casting and recasting the slow spell on them and haste on you really made things difficult. There was also no means of casting those spells on a group without beating the game at least once and getting the omnicasting augment. Buffs were the most important thing in this game. Much more than levels. you could be level 99 and lose the final battle if you relied on press x to win

Final Fantasy XII: again, buffs and debuffs are incredibly important, and you had to really plan your gambits ahead if you wanted to utilize the party effectively. And you moved around on the map, so you can't tell me all you had to do to win here was press X. And don't get me started on gambits playing for you or just hacing everyone use attack and cure - over here, it's your choice to utilize both and you havre complete freedom to figure out your own strategies against anything. It's really so much more complex and strategic than XIII it's not even funny