I'll try not to blow loads all over Metal Gear Solid's awesome bosses, but they're just great. No game captures the spirit of "old school" games with bosses with the 3D style of newer games than Metal Gear Solid (all three). I have to say though, the remake of the first one on Gamecube's not as good. Looks great, but game is far TOO easy for me. I really could write essay after essay about how great Metal Gear Solid is, and spend page after page talking about the boss battles. My favorite boss battle was probably The End or Liquid Snake, although the end all greatest part of MGS2 was fighting an army of Metal Gear Rays on top of arsenal gear. Sorry if you've never played any of the MGS games before and have no idea what the fuck I'm talking about.
Some really cool bosses, in my opiAbnion:
Separation Anxiety - Carnage - The very last stage of the game is what I call a "boss parade" every boss from the game, and then you fight Carnage on top of all of that. It was an awesome moment for me and my friend playing as Spider-man & Venom, beating assholes up and down on the 16 bit console. Venom's a great villain/anti-hero for Spider-man because he's basically the same kind of wise ass, just that he didn't have the positive influence of Uncle Ben in his life. To fight Carnage, even though I'd already kicked his ass before in Maximum Carnage, was an epic fight for a few reasons. Carnage is just such a psychotic "hitler-esque" unredeemable evil kind of guy, you just generally want to kick his ass. This game let you have two players to do that, and you fight all five of the lethal foes (or enforces, I forget), then you fight all five of the lesser symbiotes, and THEN you fight Carnage. As a guy who likes beat em up games like this, this is one of the more epic moments.
Zombies Ate My Neighbors - Giant Baby - When I first saw this, I shit bricks with laughter. Then I realized just how crazy a boss battle this would be. You can't really kill it with the bazooka weapon, and wasting a monster potion on an optional boss is a no-no as well, my strategy was to use Sodas on him (or her?) to kill it. Zombies Ate my Neighbors is THE best snes game. The greatest music, best premise, tons of levels, awesome gameplay, good graphics (my criteria for good graphics are you can tell what stuff is, and this game goes well beyond that), and is a blast to play with a friend. Furthermore, to actually beat this game is no small feat, let alone do it with a friend. I've done it by myself twice, and made it to the final boss with a friend a ton of times. Its just a great game for a horror movie fan, or really a fan of video games.
Gears of War - guy you fight at the end - Talk about a fucking cool game ending. I forget the guys name, but holy fucking shit was that a cool boss. The entire stage was one of the most epic action movie cliche' awesome moments. This guy (who is the locust general, I think), has a giant machine gun, you're on a moving train, other assholes on flying grasshoppers fly by to shoot at you, and on top of all of that, the asshole is covered in the things from pitch black and sends them at you to kill you if you step into the dark. I really thought it was a cool moment. I had to fight him on Insane to see how great it would be, and it was everything I wanted it to be. It was cheap, near impossible, and made a guy who was already a prick even tougher. Great game boss. I just wish he wasn't the only boss in the game (unless you count the three beserkers, and the big spider guy you fight)
Chrono Trigger - Lavos - Again, this is an epic game moment. If you're playing it for the first time, its one of THE greatest moments for a game player ever. You've got to fight a guy who transforms into every boss you've faught in the game, then he turns into a robot. If you follow the plot of the game at all (which I rarely do for Jrpgs), you really feel like this is the ultiamte evil going to destroy the world. And it just felt really epic.
I would mention Seperoth from Kingdom Hearts, but he literally was voiced by a faggot. I liked fighting him in FF7, but I doubt I could fight him again and not laugh about it. I loved FF7's materia system, and two bosses that deserve mention, but were entirely optional -
Final Fantasy 7 - Emerald Weapon & Ruby Weapon - I hate Final Fantasy 7, its absolutely got the most awful fan base ever. They ruined what was a great game with their constant faggotry. Sure its a great game, possibly the best (although Chrono Trigger, Metal Gear Solid, and Ocarina of Time are also my top picks) game. When I first played it, this game blowed my mind. It was back when anime was still cool so spikey haired guys with giant swords wasn't cliche' and lame, it was new and exciting. The plot had some interesting bits to it (although poor translations kind of ruined it, and thanks to a terrible fan base, I'm just even more confused when I try and make sense of the plot using online resources) It was a cool game. Limit breaks were/still are cool. The materia system was brilliant. Most of the characters (Cloud, Barret, Vincent, Cid, RedxIII, and Tifa) didn't suck ass (although two did, yuffie and cat sith) and all had backstories that tried to make them into actually likable characters. Its interesting stuff the plot. You're part of a terrorist group trying to change things at a local level, and then no surprise to anyone whose played video games before, you end up having to save the world. I don't ask much from my games in terms of plot (rarely now do I even read Jrpgs when I play them), but this one clearly delivers as a game. But even better than that, it included two complete ass-hard bosses. Unless you were really great strategist (like my black ass), you were fucked. You were absolutely fucked. Having beaten both of them a few times in different game saves, I can say honestly that they are great bosses. I developed a stratagy (which I once had on gamefaqs) that a lot of people used aparantly. My biggest brainstorm was to kill my own guys. I had it setup so that whenever they died, the phenoix was summoned and brung them back from the dead, then the other guy would hit with ultima and then the other guy hits with knights of the round twice. Do that ten times, and thats it. Thats it. Looking at it now, I don't know how I ever had the patiants to grind my characters up (let alone do it more than once. I'd estimate since 97, I've played the game through maybe 4 times, the only RPG I played more was Final Fantasy Tactics) and these two bosses are just cool. Thats that. Its a cool game, possibly one of the best, but the legions of morons who liked it have killed it for me. I'll probably never play one of the best games, because of the faggotry of its fan base.
I'm a little too ranty now. Some other cool bosses would be - Luca Blight and Neclord Suikoden 2 - Dr Wily (specifically in megaman 7) - Abyss from Marvel vs Capcom - Freddy Krueger in his nes game - Robotnick in the first two sonic games (I was underwelmed by his boss battle in the third, and disregard all further sonic games) - mother brain in super metroid - Ocarina of Time had great bosses - lot of good bosses in games.
Anyone wants to hear more rants from me like this about games, read my articles page when it goes up.