Kazuma Kenzaki defeating the Category King of Spades even after losing all of his special techniques and abilities. King says that without his cards, he's nothing and he can't seal him. After a supreme Badass Boast saying that he most certainly can, he proceeds to prove it. How? By pummeling the King's shield and HIM with his bare hands, disarming the bastard and then shattering his shield with his own sword, Dual Wielding King's blade with the Blay Rouzer, and finishing him off with a magnificent jumping slash.
Kenzaki: Even without cards, I can seal you! I'm worthy of being a Rider! For the sake of those that cannot fight... I WILL FIGHT!
After sealing King, the Trial Undead after Kenzaki comes in. Kenzaki proceeds to unleash his newly acquired King Form. Unexpectedly, because of his incredibly high fusion ratio, instead of fusing with just King Kenzaki ends up fusing with ALL the Spade Suit Undeads and delivering a brutal Curb-Stomp Battle to the Trial, ending him with a Royal Straight Flush.
Tachibana's final battle with Isaka.
Tachibana deserves an extra one for this moment: having spent quite a bit of time being worried about his body breaking down, he momentarily seems to be Isaka's servant in exchange for a certain plant that makes him more aggressive and removes the risk of destroying himself. However, once he gets the Category Ace card Isaka wanted, he IMMEDIATELY turns around to battle him. Even if he gets his ass kicked, that was pretty damn cool. And it gets better: after his defeat, he finds Sayoko dead, killed by Isaka. So what does he do? Pretty much walks straight up to Isaka's front door, ask him if it was him who did it and straight up shoot him in the face when he admits it before any kind of kung fu fight can ensue. This culminates in a showdown where Tachibana dishes out some Extreme Melee Revenge and even steals Isaka's own sword and slices him with it, finally ending with his most famous moment: Unleashing a Burning Divide while screaming the name of his lost lover.
His fight against Giraffa Undead is nothing less impressive. After dealing with Tendouji, Giraffa Undead is the last Undead other than the Black Joker aka Hajime, so the team have to make a Sadistic Choice even before the finale. Then Tachibana decides to seal Giraffa Undead by himself but he is badly outmatched (its barrier blocks his shots and even Jack Form doesn't do the trick) and was knocked down. What does he do? Shooting it point-blank where it can't use it barrier while his visor is being smashed open! And even though Giraffa Undead knocked his sealing card down the cliff (Evil Gloating included), he grabs Giraffa Undead and throw themselves down the cliff and the aftermath implied Tachibana sacrificed himself in doing so. It's his willpower and his trust in his friends which carried him this far.
Tachibana: I have lost everything, the organization, my beliefs in justice, the one I loved, and many others; that is why I don't want to lose the last thing: my friends who believe in me!
The battle with Trial G. For the first time, the four Riders all fight together, ending with Wild Chalice and Blade King Form obliterating it with a combined finishing move.
Episode 44: How the four riders lure out the Titan Undead.
The Movie ends on a rather epic battle where it ends with Kazuma cutting Jashin 14 in half in his King Form. Mind you, Jashin 14 is a massive beast, about four times as big as the Elasmotherium Orphnoch.