Jigsaw's entire plan for Adam and Lawrence in the first movie could qualify as his CMOA, considering the elaborate and mind screwing way he executes it. Also doubles as his Moral Event Horizon, when you think of the family he was holding hostage to accomplish it.
Also from the first movie, Dr.Gordon's wife turning the tables on her kidnapper to save both herself and her daughter.
Let's face it, even though he becomes the series' biggest Unwitting Pawn cause of it, you have to admit that seeing Strahm beat the shit out of Hoffman in Saw V was effing awesome.
Also, escaping an inescapable trap. With a pen.
Also, watching a medical insurance agent get his comeuppance in Saw VI...felt good.
Finally seeing the Reverse Bear Trap used as it was meant to be at the end of Saw 3D.
'I think we're breaking up with you, Dina!'.
In II Jigsaw asking Matthews for a glass of water. The delivery is just brilliant.
Matthews: I swear, if I don't see my son, I'll rip your fucking head off!
John: I don't intend to mock you, Officer, but I'm a cancer patient. How could you possibly put me in more pain than I'm already in?
In VI, Hoffman killing three cops in about five seconds, while armed with nothing but a small knife and a cup of coffee. Totally badass.
Also in VI, Hoffman's escape from the RBT, with no escape instructions. "Will to live" doesn't really do it justice.
Especially awesome considering a vocal majority of the fandom was clamoring for Hoffman to be put in the jaw-splitter to die at the time, and his method of improvised survival gained the Lieutenant a legion of fans.
In VI, health insurance executive William Easton basically summing up why Jigsaw is full of bullshit and extremely narrow-minded in choosing some of his victims.
William: Everybody thinks we're the bad guys. Nobody mentions the millions of people we help every year without incident. Or the millions of dollars we donate to charity every year. Or all the free clinics we support.
Adam revealing himself to be alive, and subsequently bashing in Zep's head at the end of part I. The Reveal made it an "Awesome Aneurysm Moment" so to speak, but then the reveal was awesome in its own way.
Simone, the survivor of the flesh scale trap from the beginning of Saw VI, attends a Jigsaw Survivor meeting in the following movie. While the other survivors talk on about how grateful they are for having gone through their tests and what a great method Jigsaw employs, Simone rightly points out what monstrous sociopaths Jigsaw and his apprentices are. The best part is when one of the survivors claims that her life's improved due to Jigsaw helping her escape an abusive relationship (i.e. putting her in a contest where she was forced to kick her partner into a room full of rotating lawnmower blades) she calls her out on how ridiculous that is.
Simone: He had to die for you to leave him?!
The mere fact that Amanda managed to be the sole survivor of a Jigsaw test was pretty badass.
Jeff shooting Amanda in the neck. After that bitch shot his wife and murdered people with inescapable traps, it was nice to see her bleeding out while Jigsaw, of all people, called her out on her horribleness.