>Gen 1 OU
Tauros + Chansey + Snorlax + Exeggutor + 2 choice picks. No customization for your Pokemon except for maybe 1 or 2 coverage options if you're lucky. Sleep is a OHKO. Normal is overpowered. Zapdos is overpowered but gets hardcountered by Rhydon and Golem. It's just not a fun tier at all once you get past the novelty.
>Gen 2
Snorlax meta. Everything revolves around how you pull the trigger with your Snorlax and how you can stop your enemy's Snorlax. Incredibly long games, longer than any other generation by a significant margin. Expect to wait 5 minutes to find a match and then spend the next 40 minutes playing through it.
>Gen 3
Toxic + Sand + Spikes. Tyranitar is everywhere and functions much like Gen 2 Snorlax, except it also effectively shuts off leftovers. But it has a lot of variety with what Pokemon are usable/useful, and it doesn't have Toxic Spikes, Stealth Rocks, or U-turn.
>Gen 4
It use-*flinch*-d to be a rea-*flinch*-lly good meta *flinch* once upon a ti-*full para*-me. But then the *flinch* OU council decided *flinch* that Jirachi and Lati-*full para*-as should be in the tier, but *hit myself in confusion* Machamp had to be *flinch* banned because *full para* the RNG bullshit was get-*hit myself in confusion*-ting out of hand.
>Gen 5
Weather wars and VoltTurn. Last gen before Fairy was added, though, so that's a plus.
>Gen 6
Insane power creep rendered most old OU staples useless. Very stall-focused due to Fairy types, especially Clefable, and hazard stacking is the entire meta. To the point where Cofagrigus is actually one of the best Pokemon in the tier because of its positive matchup into Excadrill, the best hazard remover in the tier.
>Gen 7
Fuck Z-moves. Also, fuck Magearna, Ash-Greninja, and Toxapex.
>Gen 8
Actually not that bad after all the bans. Still one of the slowest tiers, but there are a lot of unusual Pokemon like Kingler, Nidoking, and so on that have genuine OU viability due to all the defensive cores.
