YMMV / TierZoo

• Fanon: The TierZoo fan community on Reddit has invented the notion of a prestige mechanic for Outside, which rewards players for successfully reproducing. It has been hinted at in the video on Eusociality (called Genetic Percentage Points there) yet not quite fully elaborated on, but many fans will talk about a full-fledged system.
• Fridge Brilliance:
  • In "Are Crocodilians OP?", much of the crocodilians' power is shown to not just come from their powerful bites (which are optimized for grappling, not direct damage), but rather their ability to out-swim, grapple, then drag prey into the water to hamper, drown, and finish them with a Death Roll. Terrestrial crocodilians are thus Awesome, but Impractical — while it was never clearly stated in the video, the inferred reason could be that despite having land mobility and a powerful bite, they lose the crocodilians' crucial water-based advantages and efficient killing methods, leaving them outcompeted by the dinosaurs or mammals.
  • Salmon are considered D-Tier as their ability to jump out of the water only makes them susceptible to airborne and terrestrial predators like seabirds and bears. However, there may also be another reason for their low viability: Salmon are one of the most consumed fish in the world, having a terrible matchup against the strongest build in the game (humans) with several species being overfished.
• Hilarious in Hindsight: In "The Raptor Tier List", TierZoo says that "making an exhaustive bird tier list would take such a long time that I'm pretty sure by the time I'd finished making it, Youtube's algorithm would have left me behind." He would come out with a full bird tier list just three years later.
• Memetic Loser: Water Bears are frequently the laughingstock of the community thanks to their supposed invincibility ability being utterly useless against physical damage despite being immune to much larger — and statistically unlikely to ever bother them — damage, and are considered F-Tier animals. What cements their memetic loser status is that they're ridiculed by the community more often than other F-Tiers, even the less viable ones like sloths.
• Older Than They Think: He's had to break character in the comments section several times to explain that the concept of S-to-F ranked Character Tiers is not in fact his own invention, and that they go back years and are used in fields as wide ranging from videogames to professional sports.
• Play-Along Meme: The show discusses the mechanics, development, and playerbase of an MMO game called Outside. The "game" is just real life and everyone knows it, but everyone in the comments section of the videos will always talk about playing Outside as if it were a game because it's more fun that way.
• Squick: "Top 3 Underrated Animals" contains a clip of a hyena biting a buffalo's testicles and tearing them off. Most of the comments on that video are about how disturbing that scene is, with lots of viewers claiming that they felt empathy pain.

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