The finale, where Green Lantern Hal Jordan shoves a glowing, Lantern-construct stake through the vampiric Mandrakk's heart while an entire army of alternate-universe Supermen cook Ultraman alive with their heat-vision.
'I. AM. THE. NEW. GOD. ALL IS ONE IN DARKSEID. THIS MIGHTY BODY IS MY CHURCH. WHEN I COMMAND YOUR SURRENDER, I SPEAK WITH THREE BILLION VOICES... WHEN I MAKE A FIST TO CRUSH YOUR RESISTANCE. IT IS WITH THREE BILLION HANDS! WHEN I STARE INTO YOUR EYES AND SHATTER YOUR DREAMS. AND BREAK YOUR HEART. IT IS WITH SIX BILLION EYES! NOTHING LIKE DARKSEID HAS EVER COME AMONG YOU: NOTHING WILL AGAIN. I WILL TAKE YOU TO A HELL WITHOUT EXIT OR END. AND THERE I WILL MURDER YOUR SOULS! AND MAKE YOU CRAWL AND BEG! AND DIE! DIE! DIE FOR DARKSEID!'
Batman. He barely managed to survive the Black Glove's assault on him before being called in to help with the investigation of Orion's murder. His Crazy Preparedness lead him to personally take the time bullet from JLA labs so he could investigate it better himself. He's then captured by the Evil Gods and Mind Raped for weeks, maybe months as his personality, mind, and memories are violated to provide motivation for a clone army grown to serve Darkseid. Batman managed to do the impossible and used his memories to destroy the clone army from within, convince the bioweapon that was mind raping him to join his side and escape. He then manages to get face to face with Darkseid, who at this time is causing Multiversal collapse from his mere existance, delivers a Shut Up, Hannibal! and fatally poisons Darkseid with the bullet Darkseid himself used to kill his son. Batman hunted down the omnicidal god of all evil and shot him in the chest.
Wally West and Barry Allen not only outrunning Death, but leading Death to Darkseid, and then outrunning Darkseid's Omega Beams.
The normally reserved Tawky Tawny straight-out disemboweling Kalibak in one swipe. Tawny Bites!
And then, having taken down Kalibak, with no energy left, Tawny patiently straightens his bow tie as he waits for the remaining warriors to finish him. They bow to him instead, and when the irate Kalibak protests, they remind him they follow the strongest - someone he clearly isn't.
Actually, the whole series could be considered Metron's CMoA considering he sowed the seeds for Darkseid's defeat.