Hisoka taking out a RedVegimon at the very start. Mind you, Hisoka is just a human (though he comes with combat experience and does get Elemental Powers courtesy of the Digital World's creators), while RedVegimon is an Adult Digimon.
We have Tsumugi, the physically weak leader of Winter Troupe, getting cornered by a ModokiBetamon. He was terrified and equipped with nothing but a flashlight. Then he mustered up the fiercest, baddest look he could and yelled at the ModokiBetamon and turned on the flashlight. Thanks to his Elemental Powers, the light was so bright that it blinded the ModokiBetamon, allowing him to escape.
The very first Spirit Evolution by Tasuku.
Homare evolving to Vritramon and swimming out of the lava stream to fight DeathMeramon. While Vritramon curbstomped DeathMeramon, the whole ordeal is scarier and sadder than it is awesome, as Homare is taking risk with Beast Form to save himself from A Molten Date with Death.
Guy vs Homare, or should we say, Tank GoodnessThunder Beetle vs Armored Fiery Salamander. This is actually more heartwrenching than awesome due to its nature, on top of Guy doing whatever he can to help Homare gain control all while poor Homare desperately wrestling for control. We don't talk about how it ends.
Guy fighting off a group of ModokiBetamon with nothing but karate. Even Hisoka noted the elegance in Guy's fighting style.
Before that, Guy entering his fighting stance already scared the shit outta the ModokiBetamon. Just like Hisoka, Guy is a force to be reckoned with in combat, even as a human.
The entire sequence between Tsumugi and Etemon.
You'd think Tsumugi is weak and easily scared, especially after seeing how he reacted to a ModokiBetamon earlier. Then Etemon snatched the team's belongings from Tasuku. Despite having been incapacitated by Etemon's Love Serenade, Tsumugi forced himself up out of sheer anger and tried to punch Etemon, which failed, but boy, he's got balls to try such a thing against a Perfect Digimon. Etemon could perfectly kill him here if it hadn't been more focused on robbing.
Tsumugi chasing down Etemon and duking it out inside Etemon's tree house. He was so determined and furious that Etemon's Love Serenade had no effect on him. Then he proceeded to slaughter Etemon with Zoro-esque moves.
Guy defeating Woodmon. This was mainly thanks to his Awesomeness by Analysis; he knew Woodmon was slow but tough, but not without some form of Achilles' Heel. He opted to stay as a human for the mobility advantage, allowing him to strike and destroy Woodmon's eye in a blow, without taking any hits from Woodmon itself. Woodmon chose to give up instead of continuing the fight, believing that it could get worse because Guy was literally fighting as a human.
Both Tasuku and Tsumugi evolving to their Beast Form for the very first time. They immediately learned to control it thanks to Guy's guidance.
Due to his slow speed, Guy was unable to catch up with MetallifeKuwagamon to retrieve the Gold Acorn. Tasuku jumped out of the bush as KaiserLeomon and pinned MetallifeKuwagamon to the ground, saving the day and keeping his promise of not leaving Guy alone in the acorn hunt.
Guy vs Dinobeemon displays Guy's Tranquil Fury in all its glory. You don't talk crap about Winter Troupe in front of Guy.
Guy and Tasuku interfering with the clash between HerakleKabuterimon and GrandisKuwagamon and working together to take down GrandisKuwagamon. Mind you, GrandisKuwagamon is a Digimon who has transcended beyond Ultimate and is wiping the floor with HerakleKabuterimon, an Ultimate Digimon who has the longest winning streak in the Beetle Tournament. And they got away with minor to moderate injuries.
Devidramon and Musyamon may gang up on Tsumugi, but Tsumugi, possessing Holy Hand Grenade powers, made a short work of them. Devidramon was taken out with a Boom, Headshot!. Musyamon was tricked into believing that it had struck Tsumugi and sent him falling into the river, and then Tsumugi returned as Garmmon and sliced Musyamon in half.
The sparring match between Tsumugi and Hisoka is basically the two of them throwing dirty tricks at each other. Of course it is a Curbstomp Battle in Hisoka's favor, due to the difference in combat skills and experience and all and that Tsumugi still has an unhealed wound (which Hisoka hits right off the bat), but Tsumugi manages to go toe-to-toe with him with I Surrender, Suckers trick. It does not last, as Hisoka hits Tsumugi In the Back as soon as Tsumugi turns away. At the end of the fight, Hisoka praises Tsumugi for using underhanded tactics in combat.
Homare battling Gururumon and Musyamon. It's just a one-sided Curbstomp Battle courtesy of Homare having some degree of Holy Hand Grenade properties with his flames but taking out both Digimon in a punch or two? Badass.
Homare finally evolving into Vritramon and having a full control of the form, after much fear and doubts. He immediately uses his wings to fly and save Tasuku from falling to his doom before curbstomping Chimairamon.
