An ancient race of Serial Killers, now unleashed upon the world.
Kamen Rider Kuuga is one of the most well-known stabs at a Darker and Edgier take on the tokusatsu formula, and it shows.
- The resurrection of the Grongi in the first episode. An ominous humanoid figure only seen in shadow slaughters the excavation group that accidentally unleashed him, then walks slowly out into the countryside, causing trees and objects to explode with his mere presence before reviving the Grongi, causing dozens of hands to burst out of the ground like a zombie film.
- The Grongi in general. They're basically a entire race of Serial Killers. Supplemental and toyline material reveal they were once humans mutated by a mysterious meteorite metal implanted in their bodies. Which begs the question where the rest of that material is...
- All of the Grongi play by self-imposed rules of who or how they kill in their games. That means no two killing sprees are quite the same. When the police nail down a pattern, it usually means that enough people have died to leave it behind.
- Before the games started properly, Zu-Gooma-Gu (#3) took someone's place at a church. When Yusuke leaves (after sneaking inside), he encounters who he thinks is the father at the church. But as Yusuke leaves, he hears the man mutter something under his breath...and then he vanishes when Yusuke looks back. And then the camera pans away to the altar...and a pair of lifeless legs (presumable Father Hosé) sticking out from behind it.
- Me-Gyarido-Gi (#24) took great pleasure in seeing his victims as he backs his large truck into them... On that note, the fact that an ancient people quickly adapted to modern society to the point that they can operate machinery.
- Me-Ginoga-De (#26) used poisonous spores from its mouth to poison people it "kissed", causing their organs to shrink. Though not a physical threat, Me-Ginoga-De holds special mention here for poisoning Kuuga, which resulted in him clinically dying. If not for the Amadam's Healing Factor, Yusuke would not have survived at all.
- Go-Jaraji-Da poisons its victims—mainly high school kids—by shooting needles that give fatal seizures, four days after appearing to them.
- But this Grongi also has the distinction of being one of the only Grongi to make Yusuke Godai snap and go ballistic, resulting in Episode 35 holding one of the most terrifying scenes of Unstoppable Rage in the franchise. Once he finds the Grongi in the hospital, Yusuke transforms into Mighty Form while running at it, tackles it out the window, and then just starts pounding its head into the pavement, screaming the whole time. Once it starts to fight back, he summons the Gouram and then rams it, driving Jaraji all the way to the lake on the front of his bike. En route, Jaraji tries to kill Kuuga by stabbing him close-range, but Kuuga sees it coming and switches to Titan Form, shrugging the attack off. When he gets to the lake, Kuuga comes to a Screeching Stop, throwing the Grongi into the water. Then he draws his sword and slowly walks toward Jaraji (who is whimpering in terror at this point), silently transforming to Rising Titan, then slashing the Grongi and finally knocking it on the ground and finishing it off with a brutal Rising Calamity Titan, after screaming during that curbstomp as well.
- Up until this point, we've never really seen Yusuke actually get this angry. He's always nice, and wants to make people smile. Then he got pushed too far. And now, he's skirting dangerously close to being just like the Grongi.
- What makes it worse is the music. Is it a pounding battle theme? A sorrowful, reflective piece? Nope. We get a horrible Drone of Dread that lasts the whole way through.
- And to cap it all off, in the flames of Jaraji's death, we see our first glimpse at Ultimate Kuuga.
- N-Daguba-Zeba's debut in his perfect form, which is at the beginning of one of the last episodes where he has Kuuga on the ropes, belt damaged and beaten to the point that Godai can only watch as he starts setting people near by on fire in the rain. All of this is disjointedly shown to the audience as Godai would have seen it with his own eyes.
- Problem being, of course, that we don't see it. The entire first fight between them is offscreen and Yusuke bounces back from it with no problem. It kinda makes Episode 47 a bit of a mind screw considering the Previews showed us a fight between them and then...nothing.
- The style of the Final Battle: There's none of the usual epic action music. Anything stylized quickly gives way to a brutal fistfight that you'd expect from a violent action movie. Both combatants have their Transformation Trinkets destroyed. Both Kuuga and Daguva are reduced to two humans punching each other repeatedly and bleeding from the mouth. They don't stop until they knock each other out, leaving two broken forms in the snow Where It All Began.
