The hardest boss for me was Omega Weapon in FF8. I think the fight took well over an hour. I came within three hit points from losing the battle, when 3/4s of his hit points had been cut down. That battle takes the cake as hardest.
The funnest would most defantly be fighting Trance Kuja in FF9. I had been wanting to fight him for a while, but the fight with him at Pandemonium didn’t satisfy me. It also had a great song to go with it.
Well for hardest, (most annoying in my opinion) was Ozma in FFIX. I don’t like getting to super god-like levels unless I have to and this guy made me do it. I went crazy and got everyone to level 99 and roasted the spherical bastard to kingdom come.
Anyway, for the funniest, I’d have to say the Ultros battle with Relm in FFVI. There’s just something about “You pissed me off and hurt my feeling so now I’m going to paint a picture of you!” that just cracks me up. Then you get the response “What am I doing terrorizing these people for? I’m too stupid to do that! Bye!”
NOTE: I’m sure most of you know these aren’t the actual quotes in the game but for those who don’t, this is how I interpreted them.
The hardest battle by far was Omega Weapon from FF8, holy shit was that hard! at several points i was sure i was gonna die. i finally beat it when only Squall was left and his HP wasn’t looking too good. also i didn’t have any pheonix downs. i used a normal attack and he finally died. that battle really took it out of me.
the most fun battle(s) were any of the Ultros battles in FF6, some of them were so damn hilarious!
I’d have to say when I was an inexperienced gamer at the age of 10, I died a lot, especially with the first battle you get into when you’re looking for the Floating Continent…ever since I worked it out that Terra, Edgar and Mog were the perfect combination for that battle I ALWAYS used them…though it wasn’t my most difficult battle, just one of the most frustating. Same with that stupid Goddess in Kefka’s tower.
I can’t think of any that were truely difficult though…A LOT of the boss battles pissed me off and gave me problems but not to the point where I had to stop my gameplay.
thinks
Oh wait. Luca Blight. But he’s not FF 
My most fun battle would have to be all three(or four? Can’t remember) Jenova’s…I always liked the battle music when you fought that thing.
The hardest FF Boss I’ve ever faced? FFIV, Dark Elf. I forgot to equip everyone their metal equipment, and I’m not someone who likes to use Weak in a battle. It was long, and hard.
The funnest, though, was Gilgamesh.
I remember way back in the day, when I was finishing up Kefka’s tower in FF6, I had quite a bit of trouble with the Guardian. You see, I didn’t exactly have my “A-team” of characters assembled, so I ended up duking it out with Strago, Relm, Umaro and Setzer… They were all at about level 25-30. That took a few trys…
As for entertainment, the string of Ultros battles you fight in FF6. I just never got tired of whipping that guy’s butt. Mr. Chupon was awesome too.
Most difficult… it’s hard to say, since many of the games I haven’t played at all recently enough to remember.
Most fun is easy tho. Final battle of FF6. It’s hard to elaborate why, but music is definately one reason. Dancing Mad is definately in my top 5 favorite Nobuo Uematsu songs, if I had a list. And I guess the rush of just knowing that it’s the last battle. There’s more, but I don’t know how to put it in words.
hardest - the weapon in the desert in ff7 <forgets name> i found it one tough cookie
funniest - braska’s final aeon (jecht) in ff10 hah he was so stupidly easy since all my characters had such high stats - his best attack took out 41hp vs the magus sisters and i killed him in 2 attacks - how easy is that for a final boss?:mwahaha:
I thought Yu Yevon of FFX was fun because all I had to do was zombie him and he’d hurt himself. I also liked Ultimecia because I worked Squall up so much that he could take all her forms out with one turn. I’m going to try and beat the Omega weapon because I heard he was uber hard and I’d like to get a challenge. ^.^:hahaha;
The Hardest boss is gotta be Omega Weapon. Man, I tried like a hundred times but he always defeated me. My whole party was at Level 99. They had 9999 HP and still coudn’t beat him, I even got revived by Phoenix a bunch of times. But finally I used Selphie’s The End and KICKED HIS ASS!
And for the funniest is gotta be Yu Yevon, too. I mean, He totally sucked, but I still had fun defeating him, I used all I got and he died in like a minute or so. I was like training so hard, 'cause, you know, the Final Showdown or whateverl. But it was still a lot of fun!
The toughest boss for me has got to be Necron. Omega was easy for me. The only way I could beat Necron was with Steiner’s Shock ability.
One of the most fun was Yu Yevon. Zombie+Life=Dead.
The hardest would have to be one of the following:
Now the funnest…is another toss-up:
The toughest Boss? I’d have to say Zeromus from FF4. why? because I could kick the living $#!T out of every enemy in the sub levels of the moon, even the parties of 3 Red Dragons, the phantom dudes, and those head thingies no problem. Lickety split. But, when I got down to Zeromous, I got whooped BAD! So, I made sure I got up at least 25 more levels before I fought him again, then toasted his ugly ass!
As for funniest, I would have to say Palmer from FF7. I just think watching him taunt Cloud and company while they’re fighting is comical. Not to mention him almost getting his scalp grazed by the Tiny Bronco, then running off and being nailed by the Shin-Ra security truck that he called before the battle. I nearly soiled myself seeing that for the first time I laughed that hard (but didn’t though)
I don’t have a very hard boss. But the most annoying was Yunaleska. Oh god, she was so gay!! I’d always get to the final part and she’d kill my people. I couldn’t heal them because they were zombies and I had to leave them zombies or she’d do mega death! URG! It took me like a week to beat her.
I’ve always found flea to be a difficult boss, from Chrono Trigger, but ultimatly not being overly difficult due to her not so high health.
And I’ve always loved fighting Magus. He’s fun 
Shinnryuu is the hardest boss I’ve fought. That might have been my fault, since my party was level 35 and only Butz had a Coral Ring. It did beat Omega Weapon, at least.
The funniest boss? Maybe the one in FFV who kills himself if he sees you use Roulette.
Xwing1056
Hardest boss? Hmm… possibly Zeromus, or Necron. Zeromus was just so damn hard, it was a big surprise to me, I wasn’t expecting him to kick my ass so bad. And Necron is so damn random with his status attacks… Usually one of my chars gets zombied or berserked, or even that weird hot/cold status ailment. Man those were annoying.
Funnest? There’s way too many fun fights… Gilgamesh definately, he’s my favourite character in all the FF games. I thought it was fuckin awesome when he came in FF8, cause he came straight out of the N-zone!
Hahaha, that’s funny… some people that it said funniest, not funnest. Well whatever.
Hardest - Guy on top of Kefka’s town. He always casted Ultima as a final attack, which killed all my guys, until I figured out how to use life 3 >_<
Most Fun- Garland from FF1. My first RPG, and first RPG boss battle. I was like 8 so I was scared of dying. I leveled for like two months and took him down in about 2 turns.
Final Fantasy VII
FF7 wise…hm…I would have to say that the Emerald Weapon from Final Fantasy VII is the hardest. Everytime I try to kick his sorry rear-end he uses his most powerful attack and wipes out my party enitrely. Plus you only ever have 20 minutes to beat him. It’s just a pain.
The funniest…I have to agree with Mako. Palmer was just hilarious…heh, heh the part where He got hit by a truck just after avoiding the plane was really funny! Take that, fat boy!
Final Fantasy VIII
Ultimecia, Griever and her other two forms. They are so ruddy annyoing! And I hate that stupid Shockwave Pulsar!
Where is the Omega Weapon??? I can’t find the stinkin’ Depp Sea Laboratory! I know it’s near Centra, but where???
Final Fantasy X
I haven’t finished the game yet, and all the bosses seem really tricky depending on what strategies you usually use. The only real challenge for me in that game is Blitzball…
Where is the Omega Weapon??? I can’t find the stinkin’ Depp Sea Laboratory! I know it’s near Centra, but where???
Is on the South West Of the Map. Here…
http://www.rpgclassics.com/shrines/psx/ff8/map.shtml
Hope it helps…