The Saint of Killers from Preacher: He freezes Hell with his hatred. He kills the Devil. He beats a tank platoon without breaking sweat, then they drop a nuke on him. He walks out of the dust without even getting his clothes dirty and says "Not enough gun." Also killing God. Immediately preceded by the notable "Fools got in my way"... said after he's killed every single angel in Heaven.
I know it gets overshadowed by the nuke and everything, but where else have you seen a man kick a goddamn Abrams tank that was attempting to run him over, and it bounces off his boot?!
Also: "Herr Starr, I just killed a man. I don't like it, or how it makes me feel. But I did it to save your life. So just for once it would be nice if you could show some fucking appreciation!"
Jesse: Right now I'm callin' the tune an' you're dancin' for me, you murderin' son of a bitch. Right now if I say shit - you say what shape, Reverend Custer?!
Jesse finally killing the man who murdered his parents or at least his father, not that Jesse knew of his mother's survival at the time and burning down his Gran'ma's house, with her in it.
And getting his cigarette lighter back.
A hitman is hired by one of the major (human) organizations in the book, and is warned about Jesse's ability. He has Jesse cornered at gunpoint and warns that he will pull his trigger if Jesse says so much as one word. Jesse does say one word: "Miss."
Jesse Custer when he catches his former friend Cassidy's punch without flinching. Keep in mind that Cassidy is a superstrong vampire. A couple of pages later, he calmly asks Tulip and Amy to drive him to the hospital, having just broke every bone in his hand.
Later: "And that was how they killed him, covered in the ashes of his dearest friend."
Always been partial to the scene a couple pages before that, where Jesse lands the first punch on Cassidy. Not so much for the punch (though it is a helluva hallop), but how the flavor text complements it like no "Pow!" or "Sock!" ever could.
...Custer! His name reverberates like the clang of a sword. - Evan S. Connell, Son of the Morning Star.
When he breaks out of his twisted family's house and discovers that his Word of God voice works again.
"BURN, YOU FUCKERS!!"
I felt compelled to mention that Tulip gets a few in here as well. Seriously, this woman is as proficient with guns as Jesse is with his fists and far deadlier.:
One is when she rescues her friend Amy a drunken frat party rape by driving a pickup truck through the fucking WALL of the frat house and then holding the would-be rapists at gunnpoint (The fact that the gun runs out of bullets is the only thing that saves her from a murder charge). It's even sweeter when the lead rapist pisses on the floor in terror and curls up in a fetal position on the floor. The fact that this takes place during a time when she hates guns makes it doubly awesome.
She also kills a bunch of Grail soldiers during their siege on Jesus DeSade's party.
She kills a bunch of Grail soldiers during the fight in the desert using the machine gun attached to a jeep.
Hell, she takes even more out during Jesse's fistfight with Cassidy. Shit, these guys are highly trained soldiers who are considered the best in the world and she probably kills as many of them as the Saint does, and he has frickin' supernatural powers.
When she kills the intruders from "Le Enfants du Sang" in her apartment, gets biblical on them in their hideout later (Hint: Never ask "Are you Cassidy's sow?" to this woman. Just don't), and then during the final battle in the graveyard.
When she shoots Cassidy through a window after he's kept her hooked on drugs.
"I'm already carrying Ms. Featherstone's bags. You can stand to carry your own luggage for once."
Cassidy's quick thinking when in the Hacker-Slasher's apartment, who called the cops on him so they'd find him surrounded by mutilated corpses: he stabs himself in the neck and collapses so he can pull off the Body Bag Trick.