With a war going on, and the Hero and Maou on the same side, this was inevitable.
- Any time Hero fights, it is a one-sided Curb-Stomp Battle, even if he's opposing thousands of demons.
- Deserving special mention is the fight with the Archduke Fire Dragon, one of the strongest demons alive. Hero was short of breath...because holding back enough to not kill the Archduke was so hard.
- Maou does a verbal equivalent of Hero's fights on Young Merchant; defusing a potentially deadly situation, convincing him of her point of view, and apparently stealing his heart in the process.
- The return of Aurora Island and Gateway City to their respective sides by the protagonists.... on the same day.
- Aurora island is controlled by demonic forces under the South Arctic General. The Southern Kingdoms are unable to reclaim the island due to the fact that South Arctic General's army is largely composed of sea demons, which leads to a disastrous attempt at invasion by the humans. The second invasion under the Winter King succeeds thanks to the Demon Queen providing large amounts of salt for his forces to connect the floating icebergs to the island into a bridge. With the demons advantage over sea taken away, the humans can now fight them on equal ground.
- The first Aurora Island invasion failed due to the incompetence of White Night King. To make up for this, the Winter King makes Lady Knight the commander of the second. She's able to kill South Arctic General after single-handedly breaking the demons' line of battle.
- At Gateway City, Hero (masquerading as Dark Knight) wants the human Crusaders occupying the city to leave without hurting the human or demon civilians. His solution? He and the Fairies use illusions to drive them insane until their commander abandons the city with his forces, ostensibly to reinforce the Aurora Island invasion. They then encounter the retreating forces of South Arctic General.
- Another goes to East Fortress General, The Leader of the city's mercenaries, who refuses to follow the Crusader commander and stays to the protect the humans of the city by surrendering peacefully to the Dark Knight.
- Big Sis Maid (disguised as Maou) is about to be taken as a heretic. She refuses to be cowed, stops Hero from helping her, and gives a defiant speech about being "human". The church official orders her stoned, and the villagers stone him instead. He attempts to execute her but Lone Winter King and Lady Knight stop him. Lady Knight declares Crimson Scholar as a saint, and Lone Winter King places her under his protection. Finally, the officials are driven away by a shower of stones from a crowd that's cheering on the Crimson Scholar. Easily one of the most powerful and moving moments in the series.
- After Maou enters the tomb of her ancestors, she comes out as exactly the kind of being that Hero expected to meet the first time. However, before she gets more than a few steps out of the tomb, Head Maid throws her back in. She lost her left arm in the process!
- When the Hero comes in and she's still possessed, they go at it until she reasserts control over her body.
- Warrior Youngster effortlessly turns back a surprise assault from White Night Nation with minimal casualties. Then, he pulls a Big Damn Heroes moment and rescues Big Sister Maid from the Commander by allowing himself to be stabbed to gain the opening he needs to strike down the Commander. The hidden steel arrow gauntlets were pretty cool too.
- Young Merchant tricked Central into economically destroying itself by letting him buy up all of their wheat. To put this in perspective, consider that the Southern Ice General survived combat with the Hero, and commanded a powerful army of soldiers capable of wiping out a fleet of ships, and all he managed was Aurora/Bright Light Island, with little appreciable impact on the human nations as a whole. With a few canny trades, the Young Merchant did hundreds of times more damage to Central's economy and livelihood than the most powerful warriors and armies of the demon world.
- Witch Girl effortlessly teleporting an entire demon army away from the battlefield to prevent them from invading the human world. Although it's not nearly as effortless as it seems, as the manga and light novel reveal that she's laying in a pool of her own blood later as a result of overextending her powers. That doesn't stop her from using even more magic later.
- When the mercenaries Central hired decide to stage a preemptive attack, Lady Knight moves off to intercept them. She doesn't bother to put on her armor because it would take too long and she doesn't even need it anyways.
- Possessed!Maou versus Hero. Upon blasting his way into the Tomb of Demon Lords, Hero is immediately attacked by Possessed!Maou. What follows is what Hero expected the first time he showed up. Possessed!Maou even pulls the "half of the world" Hero and Maou lampshaded at their first meeting. Hero refuses, and every single one of the past Demon Lords attack him together, and for the first time, Hero goes all out. He obliterates the shadows, grabs Possessed!Maou, and burns the evil out of her. Big Damn Heroes, indeed.
- On Central's side, the Affably Evil Royal Prince Marshal kidnaps and tortures a blacksmith from the Iron Kingdom who had Maou's prototype rifle. But that's not awesome. What's awesome is how quickly and efficiently he takes advantage of this newfound weapon. In its first battlefield use, the Holy Key Expeditionary Force quickly and easily turns the battle to its favor. The Blue Ash King's improvements only make them even deadlier, not to mention that they've also developed cannons.
- Big Sis Maid's character development through the series. She starts out without any self-esteem and constantly doubts herself. Then the speech happens, which gives her more courage and independence, and even sets off on her own to learn more about the world. Upon learning about Hero and Maou being "singularities" that were supposed to die in the place of the masses, she decides that it wasn't right and resolves to fight in her own way. This "own way" involves taking charge of a band of former mercenaries, confronting Archduke Fire Dragon, and Royal Prince Marshal (twice). After she successfully talks Marshal into backing down the first time, she even gives herself the name of "hero"! Not to mention that the second time she and Marshal "fight," she successfully gets him to agree to a ceasefire and peace treaty.
- Gateway City takes a week's worth of cannon bombardment even after most of its defending forces were decimated. In-story, even the enemy acknowledges that it's not the Blue Ash King's incompetence (he is very competent, for that matter), it's just a testament to the skill and will of Gateway City's inhabitants. In fact, the volunteers in Gateway City are repairing the walls almost as quickly as they're being destroyed; their only limit is in their supplies, and that goes for both them and the attackers.
- After the Archbishop absorbs Hero's powers, Maid Chief is horrified by the Archbishop's abilities, stating that no human could have such a large amount of power... because he's actually descended from demons of the Library Clan, which Maou herself comes from. That doesn't stop Archer/Butler and Female Knight from dueling him independently. Female Knight survives the encounter, if barely. Butler has no such luck, but it is hinted that it is because of the Archbishop's fight with him that Female Knight could claim the victory later.
- After a series of introducing the human world to revolutionary new developments like potatoes, crop rotation and the printing press, how does Maou top it off in the finale? Inventing vaccinations.
