- All Adult Animation Is South Park: Played straight and averted at the same time. On the one hand, the show seemingly delights in how gruesomely violent it can get, with ludicrous amounts of bloodshed in every episode. On the other hand, the general tone is anything but comedic.
- Alternative Character Interpretation:
- The identities of the two cavemen in the flashback scene in "A Cold Death" are subjects to two different interpretations. The more obvious one is that it's Spear teaching his son how to hunt. The other is that Spear is the kid, and the older caveman is his father who has Strong Family Resemblance. Supporters of the latter idea point to slight design differences: the adult caveman looks slightly hairier than Spear, and the boy looks a bit older than the one who gets killed in "Spear and Fang". The editing does not indicate which interpretation is the correct one.
- In "Plague Of Madness", the infected Argentinosaurus starts banging its head against the chasm walls after getting temporarily stuck. Is it doing this because it's a mindless creature letting out a rage because its predicament stops it from pursuing Spear and Fang? Or is it because it managed to gain a semblance of control and tried to kill itself to end its misery?
- Awesome Art: Second only to Samurai Jack, this is Genndy Tartakovsky's best-looking show, with a visceral, "pulpy" aesthetic, some incredible character designs (some courtesy of Ren & Stimpy co-creator Bob Camp) and incredibly fluid animation.
- Cry for the Devil: The infected Argentinosaurus from "Plague Of Madness". The poor thing wasn't even malicious to begin with; it was just a peaceful herbivore who got bitten by an infected dinosaur and turned into an Ax-Crazy monster as a result. Unlike the viewer, Spear doesn't get to see it living peacefully among its herd, but still comes to the same conclusion nonetheless and looks genuinely saddened by the monster's death. The somber music that plays as it the lava flames char it out of its misery only makes it more pitiable.
- Ensemble Dark Horse: Several of the creatures that appear for one episode have gained some popularity. Such as the pterosaur from Episode 1, the saber-toothed wolves from Episode 3, and the raptors from Episode 4.
- Memetic Mutation: "I think Jack went too far back to the past", doubly hilarious, since both shows share a creator and the main characters of both shows look quite similar.
- The over the top brutality at times is unintentionally ridiculous, like the sheer beat down Spear delivers on a single Tyrannosaurus that culminates in throwing a spear like a bullet through its torso.
- In the fourth episode, as the bats attack, Fang jumps on the head of three of them in a row, which looks like a side-scroller video game. Only the Goomba Stomp sound effects are missing.
- In the fifth episode the ape-man champion Naruto runs for a fairly long shot.
- Nausea Fuel: Some of the symptoms of the eponymous plague in "Plague of Madness" are as disgusting as they are horrifying. These include flesh rotting green and dripping off the bones, pulsating pustules, and extensive vomiting of blood. Even worse, we're treated to a close-up of its flesh when Spear and Fang sneak past the infected sauropod while it's dormant.
- Nightmare Fuel: See here.
- One-Scene Wonder: Some of the creatures with cool and interesting designs have only very short screentime, after which they disappear from the show altogether. Prime examples are the Deinosuchus and the pterosaur, who both appear in the first episode before the tragedy that kicks off the plot, and the saber-toothed wolves from the third episode.
- Viewer Species Confusion:
- Viewers thought the theropods from the pilot were Ceratosaurus due to their horns, with the alpha having a lot in common with a Giganotosaurus, the granddaddy of all theropods. The animatics, however, call them Horned Tyrannosaurus.
- The sauropods in episode 6 were initially identified by fans as Camarasaurus, due to the shape of their heads. Even official sources seem not to agree on what species they are. According to episode writer David Krentz◊, they are Argentinosaurus, while the animatic for the episode calls them Brontosaurus.
YMMV / Primal (2019)