The show just kicked off, and it was All Just a Dream on the main character's part, but the first few minutes of this series definitely qualify. As the evil Bagura Army emerges from the shadows, comprised of multiple high leveled Digimon and ominous soldiers, our hero Taiki appears with his comrades, Shoutmon, Ballistamon, and Dorurumon... along with shadowed versions of Digimon heroes from past seasons. Then, Taiki commands the three to combine to Shoutmon x4, who utterly decimates the opposing army, as old friends look on in awe... this doubles as a figurative Passing the Torch moment for the franchise as well. Combine that with Taiki waking up, followed by them focusing on the legendary goggles... and then cue the opening credits.
The entirety of the one hour special of episodes 10 and 11. So, so very much. But mainly the arrival of MetalGreymon decimating everything in sight and the group Digi Xros to give the Omegamon-esque Shoutmon X4 Knight, as well as a 300-esque battle against the Bagura Army forces and DaiPenmon. Not to mention a short stint of Zenjirou wearing Taiki's goggles while he was unconscious. A special mention to Akari for snapping out of being brainwashed, attacking Lilithmon with the Code Crown, and drawing blood.
Pretty much every time Zenjirou is using the Rare Star Sword
Sparrowmon's successful determined effort to save Nene in episode 17. This is followed up by the debut of X5.
Dear lord, Episode 19 is just one Crowning Moment of Awesome after another for DarkKnightmon in the 2nd part. He destroys X4, then, as he's having a tiny bit of trouble with Metagreymon and X4, as in, not being able to land a hit, but not being hit himself, he knocks both of them out by reverting to his UN-DIGI-XROSED FORM, and literally pummels both X4 and Metal Greymon into the ground, using his two original forms, and a different Digi-Xros. Then, when the 'Invincible' Deckerdramon, Metalgreymon, and X4 all attack him at once, in a Worf Barrage and Smoke Shield moment, he is completely unharmed. And unfazed. This is the same time when it's revealed he's pulling the strings too, not his human partner, Nene, a complete first for the franchise.
Taiki punching Kiriha in the face in episode 21.
How about Puppetmon managing to surprise and bury Lilithmon, even if only temporarily? Take this into consideration: The weakest of the Dark Masters managed to bury a Demon Lord!
Taiki, armed with nothing more than a ball and chain on his leg, using it to kick Arkadimon in the chest.
Zenjirou. Episode 24. After defeating Kotemon in traditional Kendo style, he goes one-on-one with Musyamon in combat. While he didn't win, that took serious balls. Also, he gets over his fear of heights.
Episode 26- Shoutmon trains himself after feeling like he's not strong enough to be the center of the team's Xroses, and it pays off as X4B manages to hold his own against Blastmon. Then Nene and Sparrowmon show up and we get treated to the debut of X5B, who completely and utterly owns Blastmon. As Shoutmon put it, "We're rocking harder than ever before!"
Shoutmon X5 VS Breakdramon in episode 28. From the almost DBZ-esque exchange of punches, to X5 repelling several supposedly unstoppable attacks, to the heavily stylized animation where they made the fire from X5's boosters look like a cape made out of fire... It was just plain epic. Oh, and did I mention that Breakdramon was referred to as the "Ultimate Destruction Digimon", and was said to have been the direct cause of the Digital World breaking apart? Pushes the fact that X5 managed to beat him to almost Did You Just Punch Out Cthulhu? levels of badassness.
The entire battle with Xros Heart and Blue Flare against Tactimon in episode 29.
Let us elaborate- Tactimon drops a large tower-like device that stops anyone from entering or leaving the zone. He ends up hitting X5B and DeckerGreymon so hard that they separate into all their individual components. After Tactimon asks what the problem is with Digimon being revived as evil once more, since they were just “trash data that was already destroyed”...
Taiki: Like hell it is! Who said that the defeated ones were trash?! Everyone deserves a second chance! That’d be a perfect world!
Shoutmon: Taiki, you’re right! Even if we lose, it’s okay, as long as our hearts aren’t broken!
Dorulumon: As long as you believe that…
Ballistamon: We will always stand up!
Taiki and all the Digimon comprising X5 force themselves to their feet despite the gravity imposed by Tactimon’s assault, much to his surprise. Grademon shows up and performs a Heroic Sacrifice (“It’s a shame I have to do this to the new body you gave me… but I have no other weapon!”), thanking Taiki for showing him the right path, in order to destroy the tower grounding everyone in the Sword Zone.
Tactimon: You won’t get away with corrupting my underling!
Not really mention, but stuff like that is usually what causes the Main character to cause a Dark digivolution (Like in Tamers) or go beserk. Taiki is such a good person and so strong of heart, that he did not cause one. Notably he is the first, or at least one of the very few to not go that path.
Beelzemon shows up, Grademon’s sacrifice enabling him to enter the zone, and with Shoutmon’s declaration that his anger took away all his pain, Taiki Xroses them to X5B. Tactimon attempts to use his Second Strike, which paralyzes enemies with the corrupted spirits of dead Digimon, but Taiki summons the entirety of Xros Heart to break X5B out. X5B throws two of his ultimate attacks at Tactimon, which the villain almost blocks, but Greymon adds in his firepower and overwhelms Tactimon, allowing Shoutmon to finally send him flying into the stratosphere!
Shoutmon evolving to OmegaShoutmon in episode 30.
And then beating the shit out of Tactimon, complete with the full "We Are Xros Heart" theme.
Heck, it started with this statement:
Omegamon: Evolve, Shoutmon!
And what started it all was Akari and Zenjirou refusing to become Tactimon's hostages and standing up to him. Thanks to the Omegamon Digimemory, they released the powers of Courage and Friendship that led to Shoutmon's evolution!
What really needs to be mentioned is how it ends: as mentioned elsewhere on this site, OmegaShoutmon finishes off Tactimon with a move that can only be described as Giga DrillRider Kick!
Episode 31: After spending the whole episode unsuccessfully trying to convince everyone about the power of super-evolution, Shoutmon finally gets another go when he's moved by Dracomon's bravery and good heart. The army of Dragon Digimon, assuming our heroes died in the volcano, are surprised when a golden explosion lands near them. OmegaShoutmon announces his name and tells Dracomon to hide, then proceeds to completely curbstomp the army to the debut of "Evolution and DigiXros ver. TAIKI"- yeah, Dorbickmon shows up to ruin it, but Kiriha's look of total awe combined with Omega's Foe-Tossing Charge make it a great moment.
MetalGreymon evolving into SiegGreymon was one of the most badass moments in Digimon history. Extra points for Kiriha's bloody face and character development.
In Episode 35, Nene connects with Mervamon over their concern for their respective younger brothers, flies off on Sparrowmon to yank Ignitemon off his giant mount and tells him she'll beat him to a pulp if he tries to fight her, then Xroses Sparrowmon and Mervamon to JetMervamon, who summarily owns Zamielmon's beastie. Digimon Xros Wars: reminding us that the girls can be just as badass as the boys.
Taiki gets a serious awesome moment in episode 39 simply by being smart. He reveals that he has been basically playing the Death General Splashmon like a fiddle for the last two episodes, and saw through his deceptions since the very beginning. Taiki was already the smartest gogglehead in Digimon by far, but this just pushes him into another level.
In episode 41, Ballistamon killed Olegmon. By himself. He actually forced X4S to Xros Open and then soloed a Death General.
The debut of Shoutmon X7.
Not to forget the fight between OmegaShoutmon and SiegGreymon earlier in the episode.
Speaking of, special mention must be made of OmegaShoutmon debuting his move OMEGA THE FUSION, which basically takes his raw badassery and concentrates it into an aura he tackles his enemy with. Even better, that aura is Omnimon-shaped!
Same episode, little bit later: Taiki's Unflinching Walk toward Kiriha, even as the latter's Digimon attack him. Ballistamon pulls a Barehanded Blade Block against Cyberdramon, and Dorulumon knocks Golemon flat on his ass before he can even make a move!
And in the next episode, X7 utterly curbstomps Gravimon. The Death General wasn't just beaten, he was utterly devastated. If it hadn't been for his mobile core, that would have killed him outright!
In Episode 46, Kiriha shows just how far he's come by breaking Yuu's strategy wide open and proving that Xros Heart and Blue Flare's Power of Friendship is strong enough for everyone to be able to DigiXros each other's digimon. What follows is Nene commanding X5, while Taiki comes full gogglehead circle and fights Yuu and Tsuwamon with MetalGreymon, complete with Xros Heart emblems in their DigiXros sequence. It only gets better when you remember how badly the last battle Kiriha was in charge of went.
Taiki realizing that he'll have to beat some sense into Yuu and then owning him in their sword duel, ending with him snapping Yuu's sword in two and then punching him in the face! This troper cheered. And then Shoutmon X7 delivering a Curb-Stomp Battle to a beefed-up Tsuwamon.
And at that point, he had lost his Berenjena SDX and was only carrying the smaller gun he kept hidden underneath his normal one, and he was already dying due to wounds sustained earlier on. This, as he flies head-on into the face of an eldritch abomination bent on killing him and all his friends, and Beelzemon faces her down with no. Fear. Whatsoever.
The final fight against Apollomon Whispered. The villain uses his host body as a shield in an attempt to stop Taiki from fighting, but Taiki does so without hesitation, and the Digimon that make up X4 all throw their attacks at him (Ballistamon even breaks out his Ultimate Speaker!), much to Whispered's surprise. Then Kiriha and Nene show up, and X7 is formed. Whispered looks like he's about to destroy everyone with his ultimate attack, but all the Digimon on the ground below begin to cheer X7 on, and the real Apollomon forces back control of one of his arms to stop Whispered's attack. This gives X7 the chance to finish it with SEVEN VICTORIZE MAXIMUM!
The episode in the Prison Zone has a series of moments for a variety of characters- for example: Taiki, Shoutmon, Ballistamon, and Dorulumon standing up to all seven Death Generals. Even though they can only achieve X3, they declare that since it's a world of souls they're invincible due to their refusal to quit. Olegmon's defection to the good guys and eventual heroic sacrifice also qualify. Oh, and Apollomon finally getting Whispered back and one-hit killing him with the goddamn FALCON PUNCH.
One for the villains (I guess you could call it a Crowning Moment of Villainy): DarkKnightmon's epic backstabbing of Bagramon and then right in the next episode, Bagramon revealing he saw it coming since the very beginning while still complimenting his brother on a gamewell played, killing DarkKnightmon and absorbing him from the inside to become DarknessBagramon.
The final episode. Just, EVERYTHING about the final episode. Especially with the epically insane appearance and formation of Shoutmon X7 Superior Mode, by Digi Xrossing with EVERY SINGLE ALLY DIGIMON THAT EVER APPEARED IN THE SERIES, and ending DarknessBagramon in his Mega form in one stab. Easily the best Grand Finale in the entire Digimon FRANCHISE! Words fail to describe the sheer awesome this has, and never since Bokura No War Game has the franchise ever seen such an awesome moment.
The fact that, for once, it's not just the partner Digimon that are doing the fighting, but that literally every good Digimon (and if you look closely, a lot of former baddies too!) are fighting for the future of their world, many of them coming back from the dead to do so is what makes the final battle worth watching. Multiple times.
Not to mention The War Sequence that happens before hand, and several different new DigiXroses that enter the battlefield.
One for the lesser-sung heroes as well: Cutemon and Akari attacking Bagramon head-on to save Taiki. They didn't have a chance but refused to hesitate, and that takes seriously massive guts. Considering that they're two of the characters least associated with fighting it was a great moment for them both.
While it's only in the manga (and therefore a separate continuity), Akari, Zenjirou, and Nene's manga-only sister actually super-evolving Dorulumon, Ballistamon, and Sparrowmon to fight Tactimon is incredibly badass.
Taken even further when all these new evolutions end up getting Xrosed to OmegaShoutmon and ZekeGreymon, creating Shoutmon EX6. And then Starmon DNA digivolves with the Pickmons to create ShootingStarmon!
A meta example. The entire series aired in Japan with little sign of being adapted. Digimon was more or less dead in America and there was no real expectations for a dub. But now, Saban has licensed thirty episodes to dub (The entire first arc), have an ad out, and because of clips from the second and third arc there is hope of them being dubbed too. Finally, Digimon seems like it stands a chance once again.