Robert defeating the Robot Masters, Bass, and Wily in the first arc.
Of special note is a long, drawn-out fight with Ice Man that ends with the latter dying with honor.
Wily gets one when arguing with Glyde in Arc 2.
Glyde: Just give me three minutes!
Wily: You're down to two.
The MM2 Robot Masters powering up in the fortress.
Robert defeating the Megaman 2 Robot Masters, especially powerful ones like Crash Man, Air Man, and Wood Man.
Wood Man helping to purge Robert of his hatred.
Robert himself gets an awesome moment for choosing to let go of it after he spent much of the earlier arcs using his anger as a weapon.
Mega Man defeating Wily to end Arc 3, and arresting him as opposed to killing him or watching him get away.
Roll easily defeating Bass in Arc 4, chapter 1, after he had Mega on the ropes.
Rush and Bon Bonne saving Megaman, and his subsequent defeat of the Neo Emerald Spears.
Arc 4, chapter 4, has Wily, Glyde, and Protoman helping Megaman out against Quentin Emerald.
The Arc 4 finale has Wily's very convincing acting skills and scope of his plan, even in the face of reasonable doubt.
It also has Blues's brutal curb stomp of Bass.
Arc 5, chapter 1 has Robert's fights with Break Man and Magnet Man. He defeats Break Man, and with some clever planning he breaks Magnet Man's barrier, but the Robot Master's Gravity Squeeze is crushing him. Cue Roll distracting Magnet Man with an arrow, allowing Robert to finish him off.
Roll's fights against Break Man and Hard Man, where she proves she can fight with strength and strategy.
Robert defeating Break Man fairly easily in the Shadow Man chapter, using his opponent's anger against him.
Arc 5, chapter 5 has Dr. Wily not flinching one bit as Break Man lifts him by his shirt, because even if he wanted to harm Wily, Break Man is too weak to at the moment. Wily even twists the knife by calling him "Blues."
Bass's fight with Roll in Spark Man's chapter, which is much closer than the last time they fought.
Roll defeating Bass by turning his own weapons against him.
Robert goading Roll into striking the decisive blow against Spark Man before he blows up.
In Snake Man's chapter, Robert gets poisoned. He still manages to finish Snake Man off before succumbing.
Arc 5, chapter 7 has Robert using a prism orb to reflect his Mega Buster shots in many directions, destroying enemies pursuing him.
When Robert encounters Gemini Man for the first time, this exchange occurs.
Gemini Man: Even in an endless abyss, you are still as tough as they come.
Robert: The last time anyone had the gall to say that they ended up in the scrapyard.
Needle Man tries to finish Robert off with a bomb after he's defeated.
Roll defeating Doc Robot Metal Man after he called her weak. She goes into a tranquil fury mode, then an unstoppable rage. She finishes by using Magnet Missiles against him, then spiked yo-yos to break him apart.
Tiesel uses his "I am a MAN!" punch to defeat Doc Robot Crash Man, tearing through his chest and shutting him offline.
Robert and Roll arrive to the last Doc Robot area and find it deserted, with the enemies brutally destroyed. They soon find out that Break Man did it, but he'd already left by the time they got there. When he calls Robert up to tell him where to meet him, Bass overhears this and goes there to try and kill him.
Darian Darhk intercepts Wily as he goes to steal Gamma and holds him at gunpoint. Wily is unfazed by this and overpowers him, continuing what he was doing.
Bass pays Break Man back for defeating him and gets ready to kill him despite orders to bring him in alive, saying he'll tell Wily that he died fighting his own brother.
Robert then interrupts Bass, stopping him from killing Break Man, and the fight becomes a free-for-all as Roll joins the battle.
When Robert and Roll attempt to stop Bass from capturing Break Man, he says he'll take all of them on and deliver them to Wily.
Robert's battle with Bass is interrupted by the arrival of Gamma. While Robert tries to stop Wily from stealing it, his shots are ineffective against its windshield and Wily just swats him off, continuing on.
Darian Darhk tells off his mysterious employer and vows to help destroy Gamma against their wishes.
Robert uses the often-overlooked Top Spin to defeat the Kamegoro robots.
Robert and Bass's Mutual Kill late in Arc 5, which brings both to the brink of death.
Bass and Wily epically call each other out, giving each other a "The Reason You Suck" Speech. Wily even threatens to shut Bass down with a remote, but he calls his bluff and leaves without turning around.
Darian Darhk revealing the identity of the mole in front of Dr. Light, then getting them arrested.
The battle royale with the Robot Masters near the finale of Arc 5. Robert defeated them all, including some he couldn't beat before, each in creative ways.
When Mega Man is about to fight Gamma, Wily tells Glyde to evacuate the fortress as, win or lose, the government will be after them and they need to go underground.
Robert's narration when he walks in on Wily with Gamma is both awesome and funny.
I still hold my ground, my blaster aimed squarely at his face. Wily just looks at me with a grin. The grin just says "I got this here and there's nothing you can do about it".