When fighting Indramon in the city, Takato uses a homemade blue card to digivolve Growlmon to Wargrowlmon. The first thing he does is destroy the giant horn thats been kicking their ass the whole episode and then he blasts Indramon point blank with an Atomic Blaster across the city. The scene can be a considered a Godzilla Shout Out with Wargrowlmon roaring in victory.
Rika had plenty of Crowning Moments after she joined the main crew one of them being when she and Renamon had the fight and Rika being worried about her still went out to help Renamon, without having her modify cards - instead, she picked up a sharp stick not caring for her own safety and stabbed Harpymon in the back. Then there was that moment when they were fighting that other Deva wanted to get Renamon to join them, but Rika never lost her faith in Renamon enabling her to digivolve into Taomon. Then there was the Song of Sukuyamon episode when Rika and Renamon biomerged for the first time. Then the all the other times when she saved her team mates asses from the D-Reaper agents, with little to no effort, while Ryo needed help defeating one agent. The same type that Rika treats as cannon fodder. Then there is the time where she decided to look for Impmon, despite all that he had done to them.
Even before that, Rika stands her ground and helps Renamon take on Dokugumon. Rika shows Renamon warmth and compassion for the first time. She not only gets the digivolution she wants, but also thaws a bit. Subtle but noticeable.
The battle between Gallantmon and Beelzemon. After Guilmon finally came down off his Deadly Upgrade, he and Takato pulled off a miracle and spent the entire next episode throwing down with Beelzemon using attacks powerful enough to level the scenery. The first evolution of Gallantmon could easily count as one of franchise's best moments considering Takato recovered from his fear and he was the first human who merged with a Digimon. Megagargomon vs. Zhuqiaomon qualifies as well.
Beelzemon vs Gallantmon has one specific scene that stands to mind. Gallantmon (Dukemon) does the The Slow Walk (a la gohan while sounding like a giant mecha) out of (his own) flaming inferno, dons his cape (putting out the fire behind him) and declares that the devas are no match for him as he is charging his attack. No more words needed.
Guilmon and Terriermon got another moment soon after said battles. When the Big bird turned out to be not quite dead, our heroes were completely screwed. The kids were protected only by waning shield while Zhuqiaomon was bearing down on them. Guilmon and Terriermon nodded at each other and then proceeded to "jump out of the shield" to take on a beast that neither of their highest digivolutions could kill to save the others.
Gallantmon Crimson Mode.
"Do you want to fly, Gallantmon?"
Specifically, when Gallantmon Crimson Mode punches the most powerful Agent in the stomach and kills it. Bear in mind that the entity that this agent belonged to was feared by the Digital World's version of gods.
"WE DO DESERVE TO EXIST! (punch) YOU DON'T! (fatality)"
Jeri Katou has two Moments of Awesome in the Orochimon episode. First, she tells her Digimon partner Leomon "Don't worry about me! I can deal with drunkards!" when she's being kidnapped by Orochimon himself. Later, when her friends come for her and Leomon fights Orochimon, she reveals that she has a very rare LadyDevimon card and uses it perfectly despite this being her first real battle, letting Leomon finish Orochimon.
One that overlaps with Tear Jerker is when she goes up to Gallantmon when he's about to kill Beelzemon (as punishment for killing Leomon, her partner) and stops Gallantmon from doing so, since she doesn't want more Digimon to die and knows that nothing will bring Leomon back to life..
Finally snapping out of her Heroic BSOD and standing up to the D-Reaper.
Heck, just surviving and moving on after all she's been through makes her infinitely awesome in the end.
Despite the fact that it was the entire reason for him being introduced in the first place, Dobermon sacrificing himself to give the Tamers the ability to Biomerge in the Real World. Also, Alice sticking with him even though she knew how it would end counts.
Impmon's CMOA is after his Heel Face Turn, when he runs to help the main characters in the fight against the D-Reaper, armed with nothing but a toy gun given from his twin Tamers. His sheer determination to help them in order to somewhat atone for what he did allows him to evolve all the way to Beelzemon Blast Mode, and he nearly dies in a desperate attempt to rescue Juri so that he could forgive himself for killing Leomon.
"I'M GONNA SAVE YOU JERI, IF IT'S THE LAST THING I FREAKIN' DO!"
"FIST! OF! THE BEAST KING!!!"
Henry's father Janyu Lee deserves a mention for demonstrating true martial arts in the episode "Boar Wars". He's so fast most missed it. Trully a hidden Badass Bookworm, with a labcoat to match!
Terriermon gets one for being the first- and so far only- partner Digimon to be the first to evolve, while not being the main hero's partner.
Guilmon gets a few moments:
In the 3rd episode seeing his fights with Renamon. He is entirely unaffected by Renamon's Diamond Storm, just standing there ignoring it. Later episodes show Renamon defeating Champion level Digimon with the same attack.
His fight with IceDevimon definitely qualifies. After Kyubimon suffers a defeat, Guilmon gets a boost from Takato's Modify cards, and slams IceDevimon's head into the ceiling then blowing him to pieces with Pyro Sphere. The victory is even sweeter seeing Ice Devimon's arm hit the ground before dissapearing.
Wargrowlmon defeating Vikaralamon.
Once Takato realizes Guilmon will always be the same regardless of how powerful he becomes, Takato begins channelling power to Wargrowlmon. Wargrowlmon breaks free from the power orb holding him down the whole episode and charges Vikaralamon, tearing through another power orb in the process. He grabs Vikaralamon by the tusks and begins pushing him back, a pig larger than all the buildings around him. Then after the other Tamers Digimon perform some clean up control, he flips Vikaralamon over and finishes him off with Atomic Blaster.
Zhuqiaomon gets one when he's the only Digimon seen in the Digital World fighting the D-Reaper days after the Tamers left the place.
There were originally dozens of Mega level Digimon ready to fight the D-Reaper which includes replicas of Big Bads from previous seasons Metalseadramon, Machinedramon and a few Diaboromon. None of them were seen after that.
Grani on a constant basis.
When he shows up in the Real World and him and Gallantmon kick the D-reaper's ass their first time.
Also his You Are Not Alone moment with Jeri in which he actually talks her out of her Heroic BSOD that she's been having for the past several episodes! What makes it extra awesome? He pretty much talked Jeri out of commiting suicide!
A Big Guy, Little Guy moment when Impmon and Calumon team up to save Jeri in episode 46. Calumon rushes to find Jeri while Beelzemon acts as The Big Guy against the D-reaper agents in their tag team.
The 3 Tamers bio-merging to Mega level for the first time in the Real World. They're able to put aside their worries to fight for a cause and kick some D-reaper butt.
Takato and Guilmon's last bio-merge digivolution to Gallantmon before setting out to the final battle with the D-reaper. He jumps on Grani and gives a final goodbye to his parents not to worry. Even his parents think he looks awesome.
The monster makers final plan to defeat the D-reaper. To devolve the D-reaper they installed Juggernaut into Megagargomon to use in the D-reaper's weak spot. But in order for Megagargomon to pull it off he had to create a spin faster than the freaking speed of light! He does...
Dukemon in the Japanese version goes from being an adorable goofball as Guilmon to a hotblooded, noble warrior with a deep and commanding voice. This characterization made his scenes all the more impressive, especially the Beelzebumon fight.