Conflict is what makes most games/movies/books work. I was a little bored and shuffled through some of the best and worst of those moments.
Kelsier vs The Lord Ruler
The good guy confronts the big bad emperor who killed his wife and imprisoned him. Everything in the entire series builds up to this moment, in spite of it happening late in the first book. It works well on a couple of levels. Both for the clash of personalities. Kelsier and Rashek are very similiar in terms of execution. Both do what they think is right and best for humanity and let morality be damned- Kelsier overthrowing the final empire and executing nobles, Rashek killing so the so called savior of the world and forming the final empire. They are two sides of the same coin and are fighting for the same thing.
Both also end up creating religions where they are the the savior/hero of the world. Both end up being right in their own way. The actual result of the fight isn't what you expect, but it makes perfect sense. The Lord Ruler slaughters Kelsier and breaks up the rebellion he's stirring up there, at least for the moment.
Rand vs Rahvin
Rand has several duels with forsaken to end various WoT novels. This isn't the biggest of these (Rand vs Ishamael in book 2 likely is) and it's not the strongest powerwise (Rand vs Asmodean). What the fight is several stories- Rand/Lanfear, Moiraine's destiny, his fear of women dying, and his increasing lack of sanity/normal emotion coming together at once.
Which is funny, as Rahvin then kills his best friend and Aviendha. Shit hits the fan and Rand scares at least two forsaken shitless (Not including Rahvin and Grendael) with the resulting fight, which is one of the best in the series. I consider fires of heaven to be the best book in the series, and that fight is the peak of the book.
Joshua vs Yuri
This is notable just for Yuri's reaction if you bring Vandal Hearts. He's your typical best friend turn nemesis, who you fight at the end. You can save him if you get Vandal Hearts, which is an excessive pain in the ass to get in VH2. You manage to get him to actually reverse ground and rejoin the good guys, which is a nice change of pace from the usual fight/death you get if you don't have VH there.
The Devourlord vs Endorph/Odie/etc
"I wanted you to be here for this." If you've done the demon path, you know which scene I'm talking about.
Creasy vs Sanchez
Most movies have excellent confrontations. The Dark Knight is one of many off the top of my head. I chose this one because the entire movie is built around one scene that happens at the end.
Creasy is a bodyguard hired to protect a child, who he gets attached to. Sanchez is someone who kidnaps her. The scene is just the climax after two pretty brutal hours in general. Watch Man on Fire.
Worst:
Roland vs Crimson King
The Dark Tower has three top tier books, one that is great but gets a mulligan due to not advancing the story (Wizard and Glass), two so-so books and one that is equal parts excellence and XS3 level terrible. The Crimson King is Stephen King's ubervilllian, basically his universe's version of satan. Roland is his ultimate knight, who spends countless years and miles wandering to meet and fight him at the base of the dark tower.
What do we get? A motherfucking old man throwing Harry Potter toys (Literally, sneeches) at Roland while a mute artist kills him by erasing his face. What the fuck. In a book that had the author inserting himself into the world, blatantly killing off important characters for no reason and completely pissing on the legacy of a seven book series, this may be the worst part of it.
Steven Deschain vs Randall Flagg
Randall Flagg. Villian of The Stand and in a couple of King's other works. He is eaten by the demonic spawn of Roland and Susannah Dean. What the fuck.
Reality vs Shion Uzuki
The person responsible for literally destroying the universe makes yet another selfish, whiny choices and betrays humanity and her friends to join up with the man who caused her extreme mental trauma and did god knows how much damage because he tells her she's pretty and that he luvs her. Awwwwwww. Not breaking news, but everything about the scene before you fight her is absolutely terrible. It's XS3 disk 2, but even by those standards it is awful.
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All of my worst confrontation moments are from longrunning series that absolutely tank at the end. This makes some sense, as only a serial novel/game could really get the length and character depth required to really fuck up a scene.