Would've put this up yesterday, but I hadn't finished Resident Evil 5 yet, now I have, so I feel ok with this list. Presented in order of how awesome the fights are. (Contains RE series spoilers!)
5) Alexia Ashford I, Resident Evil: Code Veronica The first time you fight Alexia, she hasn't yet mutated into a giant bug-thing yet. She has, however, just schooled Wesker, and that means trouble for Chris. With the right weapon (read: a magnum) she goes down relatively easily, but her fire throwing and acid vomiting means you have to be in constant motion not to get burned up.
4) Right Hand, Resident Evil 4 The Right Hand is like a combination Alien and Predator, with a little T-1000 thrown in just because. The only way to kill it is to freeze it with liquid nitrogen, the shatter it. This is easier said than done. Of course, if you keep that rocket launcher you find earlier for this fight, you won't have much trouble. That and the fact that you don't have to defeat the Right Hand to move on keep him low on the list.
3) G-Type 2, Resident Evil 2 You might think you've taken care of William Birkin, but you're wrong. While escaping the police station on a giant tram/elevator thing, he comes back, and he's mutated more. And he's pissed. He grows a giant Tyrant-style claw and comes after you. He's tough, and even a magnum takes a bit to bring him down.
2) Tyrant, Resident Evil The original final boss, this guy is still an icon of the series. A superhuman monster with a claw where his right hand should be, you take him down in the lab, after he kills Wesker. Or so you think. Both Wesker and the Tyrant survive, Wesker escapes, and the Tyrant comes to the hellipad for one last ditch effort to stop you from escaping. Only a rocket to the face stops the Tyrant.
1) Jack Krauser, Resident Evil 4 Let's be honest, the final boss fight in RE4 is a little weak. Saddler goes down like a chump if you've been managing your ammo at all. Krauser, though? Krauser's a bitch, even with a fully-loaded magnum at your side. First you have to deal with him and his machine gun, then you have to deal with his plaga-enhanced physique. And arm blade that doubles as a shield repels anything you toss at him. He's the baddest boss of the series.
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