Final Fantasy - The most obvious choice would be Garland since he's the first boss and secretly the final boss, but I feel Lich would be the first boss to really look out for as he tends to be the first "gloves off" boss that FF throws at you and his infamous arrival as a random encounter is still one of the game's more brilliant moments.

Final Fantasy II - The bosses in this game are not as memorable for me except for one, and that's the series first encounter with the infamous Behemoth in the Coliseum which is a pretty stellar battle if you don't over-level early. Lamia Queen is also a pretty memorable as well if only for the events leading up to it.

Final Fantasy III - This was pretty easy, Garuda is probably the most infamous boss in FFIII outside of the boss gauntlet in the end game. Garuda was popular enough to become a summon later as well.

Final Fantasy IV - Part of me would love to give this to any of the Archfiends, most likely the final battle where you have to fight all four of them in a row, or I could give this the Dark Elf, who was a pretty spectacular battle after one of the game's most infamous dungeons. But I feel there is only one real answer here and that's the Demon Wall. This boss was such a nightmare for fans that SE loves to bring it back just to terrorize us. I think this boss has killed me more times in my early playthroughs than any other in Final Fantasy.

Final Fantasy V - This was probably one of the toughest because frankly, I feel FFV has the most creative and interesting boss battles in the franchise likely short of the MMO entries. I may give this to Atmos since this boss is a real bastard even if you know what you're doing. It's also just a creepy fight much like the Demon Wall where you watch your poor party members get lost into the void throughout the battle if you don;t revive them quickly enough. Not surprised he's made a few appearances down the road.

Final Fantasy VI - Easy picks here would be the various Ultros fight or the Ghost Train, but I'm giving this to the debut of the Ultima Weapon who pretty much was a perfect boss to segue into the Ruined World. So good in fact, most people forget he's not even the final boss of the World of Balance. Cool animation for him and the introduction of Flare Star and most likely some players first chance to see Quake, Meteor, and Flare. He's a really nasty piece of work for unprepared or under-leveled party. Sure there is a rematch fight later, but by then your party is so souped up from Magicite steroids that he's just a blip on the radar to the final boss.

Final Fantasy VII - This was a bit tough for me, largely because I'm trying to avoid story-centric villains on this list and most of VII's most memorable boss fights are ones with major players in the script. Jenova for instance is an easy pick and I would likely choose the battle against her after Aerith is killed but I feel Jenova falls a little too close to "main villain" territory so I won't count her (though anyone else is free to) s for not important bosses, I may give this to Carry Armor as it was one of the few bosses that gave me a game over in my first playthrough, though I also loved the Guard Scorpion as well. Yet I think my favorite fight is still the one against Rufus on the Shinra HQ roof. Not necessarily a challenging fight, but one of the more cinematic ones.

Final Fantasy VIII - This one was pretty easy. X-ATMO92 is one of the most memorable boss battles in the game and was the star of the game's demo. This was just a creative fight with a lot of cinematic and quirky elements going for it. Easily one of the most memorable parts of the early game and probably the most creative boss in the PS1 era.

Final Fantasy IX - Hardly the most challenging fight but the battle with Black Waltz #3 is easily one of the coolest moments in the first disk and unlike all the Beatrix battles, is actually winnable. My second choice would be Zorn and Thorn since I love the fact they use Twin Magic. For a non-story relevant boss, probably Gizamaluke or Ark.

Final Fantasy X - Not a huge fan of the bosses in this game, probably Chcocobo Eater since if like the gimmick for the fight, or Sanctuary Keeper since he's one of the few bosses in the main story that can be pretty tough if you go in unprepared. For a more story-centric boss, probably Yunalesca, especially since multiform bosses are rare outside of final bosses.

Final Fantasy XII - Part of me wants to give this to Elder Wyrm, especially since its the last boss in the main story that will likely give players a hard time unless they actively avoid doing all of the side content. Yet I may really give this to Belias, especially since he's both a pretty nasty fight on his own and the FFTactics fan in me always appreciated this battle since he was probably the most memorable boss fight in Tactics.

Final Fantasy XIII - Ugh, probably the toughest one for me since I hate this game. I may give this to Proudclad since I like the reference to FFVII and because I probably died to this boss more times than any other in the game except maybe the first Barthandelus fight. Mainly because I was stubbornly trying not to use a Synergist.

Final Fantasy XV - Probably the Malboro. That whole chapter is one long giant player punch, but I have to give XV props for really creating a cool and atmospheric build up to the usual "Oh trout" moment that is encountering a Malboro. It's a pretty challenging fight as well since you're effectively handicapped for it with only three effective party members and no access to good food buffs. Leviathan is probably the other big one most people remember but that fight is pure cinematic and like the final boss fight, is mostly a button masher.