Per wiki policy, Spoilers Off applies here and all spoilers are unmarked. You Have Been Warned.

Chapter 1:

Sougo wasting no time in showing why he's capable of taking over the extremely Crapsack World of Drakengard by easily wiping out a group of soldiers who attacked him OUTSIDE of his armor.
Soldier: Who are you?”
Sougo: Who am I? I am your king, so bow to me and I might show you mercy.
Soldier: You? A king? Don’t make me laugh! How do you expect to be king when you’re about to be dead?!”
Sougo: Don't mistake my fate for yours.
Oma Zi-O managing to deliver a brutal No-Holds-Barred Beatdown towards Zero of all people even after she enters Intoner Mode to level the playing field.
Zero's reaction to Dragreder dragging Mikhal away for a fight? Threaten to rip Oma Zi-O limb from limb if he dares to hurt Mikhal. Please note this is while she's been beaten to near death and struggles to even crawl, yet still has the guts to say this to the man that did this to her.
Oma Zi-O telling the Watchers, aka the Eldritch Abomination servants of the gods of this world, to basically go screw themselves and that this world is HIS to rule.

Oma Zi-O actually Rapid-Fire Fisticuffs Dito to death about almost casually No Selling his stab. Its so effective that Dito is reduced to just a head after everything is said and done.
Zero outright refusing to simply be an obedient concubine and servant to Sougo and demands that he gives her the respect he expects to give others around him at all times, king or no.
Zero: Let me make this very clear to you here and now: I will not be treated like your slave, I will not go back to that life, and if you think you will just boss me around like I'm some toy or some broken in house pet, then kill me now. I don't care what kind of power you have, or what you're packing, or even if I owe you my very fucking life. I would sooner die trying to gut you than be humiliated by the likes of you or anyone in this world or the next. Are we crystal clear on that, Sougo Tokiwa?
- She gets exactly what she wants, with Sougo treating her - and by extension, her sisters - like true partners and lovers, instead of simple harem members.

Castle Doran laying waste to Four's skyship forces all by itself, with no ship that comes at it able to do anything but barely slow it down.

Oma Zi-O responding to Three summoning Armisael by summoning Kamen Rider Build and Kamen Rider Hibiki. The following events leads to an EPIC Break the Haughty sequence for Three, which is made more potent given the fact she was so assured of her own power and abilities, planning on turning Sougo into a doll like she did with her subjects, only to realize all too late that she SEVERELY underestimated the King of Time.
- Kamen Rider Build needs to be a lot of love for actually undoing the experimentation done to the citizens of the Forest Country performed by Three, proving he's THE Science Hero of Kamen Riders.
- Kamen Rider Hibiki managing to hold off the doll army before going into his Armed form and going on to knock out Three with his BFS Finishing Move.

Sougo actually managing to beat One of all people in a truly philosophical and psychological game of chess.
One: ...I see. Perhaps fifty years of experience is just as impressive as it sounds.
- For the context, the above line is right after One realizes the trap she allowed herself to fall into, otherwise known as the King's Gambit.

Four laying the fuck into One for hiding what she knew about the Flower and willing to let Zero kill her sisters AND for hiding a brother the entire time.
Two actually showing that her backbone matches her moral fiber and calling out Sougo for putting the world he aspires to rule over at risk by being willing to call the Flower into the world to fight it.
The Intoners actually working together and stopping the Flower from being able to use the Song.
After waking up from the Flower's Mind Rape, Oma Zi-O summons female Kamen Rider weapons to help turn the tide of battle, with each Intoner wielder their respective weapon with great efficiency; from Five and Three long-ranged devastations to Four basically becoming a deadly and lethal dancer on the battlefield, to One and Two growing wings for upclose, airborne attacks, to Zero summoning a feather tornado to finish the job, it was clear that the army the Flower created was no match for the originals.
Oma Zi-O destroying the Flower once and for all with a ungodly Rider Kick.