Luther averting Black Dude Dies First by somehow surviving being dragged away by zombies to emerge from the sewers kicking ass. "Star Power, Bitches!"
Bennet, in the climax, goes to reach for Alice's gun to stop her from fighting back against Wesker. As he reaches for it, K-Mart grabs the gun. He asks, "Who the fuck're you?" She answers by pistol-whipping him cold.
Alice putting the nuke into the V22 that Wesker jumps into to escape at the end of the movie. His eyes light up and his face remains the same, aside from the aforementioned eye light, but you can tell that inside, he's yelling "FFFFFFFFFFFFFUUUUUUUUUU-!!!!!" at the top of his lungs.
The filmmakers deliberately wanted to make this one seem more faithful to the games and address complaints about the other movies. The Executioner, Majini, Wesker, Jill with the mind control spider, and that shot-for-shot remake of a Resident Evil 5 cutscene are crowning moments of awesome for them.
Even more epicness in the final boss fight. Alice shoots her shotgun filled with coins at a dog. It kills the dog and the coins hit a window at the top of the area. A dog jumps at her while the glass is falling. She brings her leg up, and kicks a shard of glass at the dog. It kills it. Later on, Wesker is about to eat Alice. She takes the shotgun and shoots him, blowing a hole in his head. After that, Wesker is starting to get back up. Alice notices this, but Chris pushes him down, says "I don't think so" and Chris and Claire unload their pistols at him.
And he SURVIVES ALL THAT, PLUS the above mentioned plane nuke! They definitely kept Wesker as powerful as possible.
Afterlife opens with one of these: Wesker versus Alice. Let's put this into context, shall we? Over the course of movies 2 and 3, Alice has gone from the Badass Normal she was in film 1 to a full-blown God-Mode Sue (even Black Hole Sue by the third film), who could win a fistfight with the friggin' Nemesis, had Psychic Powers that she got from the T-Virus, and constantly stole the spotlight from canon badasses Jill Valentine and Claire Redfield. She even assembled a clone army to take on Umbrella. So, what happens in film 4? As the clones go into Umbrella's Tokyo HQ, Wesker guns down two clones, evacuates to a Cool Plane, leaves the facility and nukes the entire clone army. He's then jumped by the original Alice on the plane...and he proceeds to tell her that it's nice to finally meet her, catches her off guard and injects her with a serum that permanently removes her God Mode powers, and then kicks her ass from one end of the plane to the other. Yes, fans, Wesker literally beat the Sue out of Alice. It. Was. Glorious.
You know you've made some misteps in the franchise when your hero getting the everloving shit beaten out of her is considered the most awesome thing in the film.
As further evidence that writer/director Paul W.S. Anderson is learning, Claire goes from doing... pretty much nothing in the third movie to having a legitimate Moment of Awesome of her own here, namely her fight against the Executioner Majini in the prison's shower room. The fight tears the room apart, and climaxes with Claire grabbing Alice's dropped sawed off shotgun, sliding toward the Executioner and shooting him point blank in the chest. True, it only puts him down temporarily, but it was still awesome
Followed by Alice reawakening and the two pulling of Deadly Dodging to disarm the creature, and then proceeding to blow his head off with the other shotgun
Wesker headshotting an Alice clone while she was freefalling!
And then coolly walking away from the explosion caused by the second Alice clone trying to invoke a Taking You with Me with only a few bruises