Lex Luthor's betrayal of the light, if only for how casually he managed to throw the team and the light for a loop.
The attack on the watchtower. For the first time in a while, the mooks aren't easy for the league to take down, and it is a glorious battle for survival.
For that matter, they managed to give Dr. Fate and Hal Jordan, two characters with a big Story-Breaker Power a hard time.
Ms. Martian, Wonder Girl, Superboy and Wolf make a desperate escape from Smalville from another army of parademons and suicide jockeys.
On the villains side, Kara's brutal beatdown of Superboy. Though he might fight like a kryptonian, Kara really didn't give him much room.
The fight for the future. 5 years into the future, the remnants of a new Team escort Bart Allen to his time machine to return to the past and prevent Darkseid from destroying everything. Facing Parademons, a being with kryptonian and maritan dna and evil wally, they fought to the last man, and even in death, the last 2 members faced it with honor.
Klarion's surprisingly forward thinking in leaving some residue magic so he can turn Roanoke Island into a magic fortress to Drain Raven of her powers.
The Car Chase and battle between Nightwing, Starfire and Red Hood's boys.
The battle in DC. Risking everything to save the future, the team exposes Godfrey as the fraud he is, stops the league's suicide attack, and a battle with the furies and their armies begins. The Justice League even gets in on the action, making this the first full scale brawl that needed the league and team since the reach endgame challenge.
For that matter, there's Blue Beetle taking down Lashanna on his own.
And finally Kara cutting ties with Apokalips by defeating Big Barda.
The day of battle against apokalips is literally littered from top to bottom with awesome moments, considering it was earth's Last Stand against Darkseid.
Red Hood, Arsenal, Jinx, Red X and Guardian entered the floating space station, fighting hordes of security drones and parademons in an attempt to destroy it once and for all.
Perhaps most key was Red Hood and Arsenal's fight against Steppenwolf, where they managed to knock him out with the old "explosives on the back" trick.
As they made their escape, Jason put on the crown of war world, putting himself in great pain, but also allowing him to take control of the security drones in order to buy them more time against the parademons.
The wonder family vs The Furies.
Donna Troi, the previous Wonder Girl fights and ultimately defeats Lashanna with a Single-Stroke Battle.
Cassie drags Volcanna into the sea in order to defeat her.
Wonder Woman vs Barda. Two heavy hitters going all out. Wonder Woman even manages to repay the favor to her by dislocating Barda's shoulder like she did in their first fight.
Granny Goodness vs Themyscira. While a non-action general at first, she ends up tearing through the amazon ranks, and even defeating Wonder Woman in 1 on 1 combat.
Aquaman vs King Shark. The 2 kings locked in battle with the fate of a kingdom resting in their fight.
Black Manta's Villainous Rescue and the subsequent Enemy Mine was also rather cool if only because of how well they worked together to drive Nanue off.
For that matter, Manta's Kansas City Shuffle to escape prison during the battle. "Nobody leads Black Manta's army but Black Manta."
This WAS the Final Battle between the League and Klarion. The most powerful member of the light locked in battle with Dr. Fate, Ms. Martian, Zatanna, Wolf and Beast Boy. However, with Raven's powers on his side and with Teekel running interference, the heroes were hard pressed to even make a dent in Klarion.
However, it's only when all the others are pinned or injured that Beast Boy steps up and turns himself into a Spinosaurus to fight Teekel on more even grounds. Even better, he uses the technique Superboy taught him to unbalance the cat, then went dino again to break his neck!
Raven unleashes her powers on Klarion, even giving him a glimpse of her father trigon in order to finally warn him not to mess with her ever again.
The rescue mission for Wally West is pretty awesome. Perhaps the first awesome part of it is that it was a Call Back to the older days of the show, and was the only real mission that involved sneaking around to reach their goal.
Red Arrow and Cheshire as a Battle Couple. None of the parademons could even touch them.
Artemis and Bart's battle against Wally was pretty awesome because Wally got a speed boost, so he could now run at Bart's speed. Yet it's not even Bart who manages to incapacitate him. Rather, Artemis was the one who managed to do it, even though it involved putting an arrow through his knee.
Superboy VS Doomsday. While Conner was pretty outmatched even with his new TTK, he fought tooth and nail against the Kryptonian killer, even exposing his heart by ripping off the many crystals on his body.
This however lead to the Big Damn Heroes moment where the Superboy was saved by Supergirl and Superman right in the nick of time.
And of course, then there was the subsequent super family vs Doomsday fight, ending in his death from 3 Super Strength punches to his heart.
Cyborg vs Gizmo. Victor Stone finally has his confrontation with the man who made him a part robot. Surprisingly, it's hardly even even, as Cyborg incapacitates him rather easily.
Yet few things were quite like the Final Battle against Darkseid himself. He cements himself as a Badass in this universe when he manages to fight Nightwing, Starfire and 2 green lanterns at once. Green Lanterns!
Which in turn requires 3 Big Damn Heroes to save everyone. Cyborg, Batman and Superman all come in at different times to help save the day and keep their team alive.
One has to give props to the author for creating a story that not only provides a more satisfying conclusion to the series than we got, but also managed to weave his storylines together in such a way that it feels just like the show proper in execution, mystery and intrigue.