I'm going to group slightly when there's more than one boss from the same game that I feel deserves a spot.
5.
Khidr (and some others) -
Rogue Legacy, 2013While most of the bosses of Rogue Legacy are my kind of fun challenge (except perhaps Herodotus, who's just a pain, and the remixes of Alexander and Ponce de Leon), Khidr holds a special place as the first real challenge of the game. Everything you do before then you can bumble through quite happily, but when you get to this fellow, you have to step up with your dodging skills if you want to survive.
Other mentions go to Astrodotus, who plays like an Asteroids game, and it can be pretty tough keeping out of the way when every time you hit him, he breaks into two smaller pieces and gets faster. Even keeping pieces to a minimum, you've still got a lot of bits flying around to dodge, and you can only get hit about three times. Also shouting out to Neo Khidr, the remix of Khidr. Basically the same fight as Khidr, but much harder; he shoots faster and tighter and you can only get hit five times, meaning if you want to live, you've really gotta train with those movement runes.
4.
Dark Link (and
Thunderbird) -
Zelda II: The Adventure of Link, 1988I would be reasonably comfortable in saying that this is probably the most challenging end boss of all the NES games I've played that doesn't feel cheap. Assuming you're not fighting him the exploit-y way, beating him is quite an endurance fight. You've gots to keep trading blows with him, most of which you'll both block (ideally), and wait until he jumps and opens himself up to a stab, which even then can be tricky to land. I think this deserves the spot just because it really does feel like a proper duel; neither of you have any real advantage over the other.
Also throwing out the boss fought immediately before Dark Link, the Thunderbird. It just flies around the screen in a fairly predictable pattern constantly spitting fireballs out. That said, it's damn fun having to dodge those fireballs (which really quite hurt) to land your hits. Especially when at the halfway mark, the rate at which those fireballs come out goes up dramatically. For the real challenge, you get to that point with the single point in Attack that you started with. I counted how many times you have to hit her once, but I can't remember how many it was. Somewhere in the 50's, I think? Maybe around 100. Lots, either way. And when half of that time the fireballs are rather raining down, it's tough!
3.
Dragon Zombies (and
Dracula) -
Castlevania: Circle of the Moon, 2001I'm not sure why this boss strikes me as so memorable. I suppose it's just got a very nice balance of challenging and fun. And also it's a pair of zombie dragons. It can be tough keeping track of what both of them are doing, and you have to, otherwise while you're trying to keep out of the way of one, you can get a nasty bite from the other, and they do hurt.
I'm also shoehorning Dracula from the same game into this spot. I've fought Drac in a lot of Castlevania titles, but the one in Circle of the Moon is one of my favourites. He's not too hard, but not too easy (with one attack in particular that is almost certainly OHKO, and needs good timing to dodge), and
the music for the fight makes it feel so... epic. And I do not use that word lightly.
2.
The Nightmare -
The Legend of Zelda: Link's Awakening, 1993I really can't say why this is so high on my list, but it is. There's just something about it.
1.
[Various] -
Monster Hunter Tri (Ultimate), 2009 (2013)I tried to pick some MH3U representatives, but there's just so many great ones, it is basically impossible to decide. Pretty much every large monster can couunt as a boss, and most of the time, they're what you're fighting. I suppose I can at least pick out some specific reasons.
Rathian deserves a mention, because that's the first real "oh shit" moment. You're fighting a 'Peco, as per usual, but when it goes to call another large monster, as it does, it lets out a different, quite powerful roar. Foreboding sets in there, but you keep fighting and for a bit nothing special happens, the foreboding eases just in time for a MASSIVE GODDAMN DRAGON TO LAND AND SET ITS SIGHTS ON YOU.
Deviljho would be the other major "oh shit", as it is a huge,
hungry beast that will drop in in just about
any quest after you clear the low rank quests. Effect amplified by the new
tense orchestral music that accompanies it. And then, as though Deviljho wasn't, there's a
Savage Deviljho.
And what about Jhen Mohran? A battle from a ship against this colossal leviathan over 100 metres long?
A special mention to Lucent Nargacuga, a rare species of a monster you'd know well to be very fast and powerful, which has the delightful bonus of being able to turn invisible and shoot poisonous spikes out of its tail along with nearly every attack it makes.
Special Mentions (in no order):Robo-Manus -
Battletoads, 1991: Damn fun to fight! He'll jump around. If he lands on you, you die instantly. When he lands, he'll shoot three shots, and if you're not ducking or jumping, that'll probably kill you too. To this day I've never been able to juggle him for long enough so that he never touches the ground, but one day...
Big Mouser (and the
Technodrome) -
Teenage Mutant Ninja Turtles, 1989: Big Mouser is piss easy, but is still a cool boss. The Technodrome is good fun too.
Death -
Castlevania: Simon's Quest - 1987: The only reason this guy is being mentioned is because you can kill him with garlic. Unfortunately, I don't have a video to show why that's funny.
The Evil One -
Faxanadu, 1987: He's just cool.
Smithy -
Super Mario RPG, 1996: Because it's a fun fight, and has
good music.
Ugh-Zan III -
Serious Sam: The First Encounter, 2001 (/ 2009): Similar reasons
as above.
Makron -
Quake II, 1997: Because it's the Makron.