Red/Blue: You run around bullying kids so you can go beat up adults and oust the champion from his full time job with your fire dragon

Gold/Silver: You have a really evil rival and team rocket fires probably gamma rays at every Pokémon ever giving them bad radiation poisoning but they look cool so it’s ok

Ruby/Sapphire/Emerald: You find out that these evil teams with no ability to color coordinate orbs have woken up literal terraforming monsters because.... reasons?

FR/LG: It’s like gen 1 but with gen 3’s trumpets

Diamond/Pearl/Platinum: Once again an evil team with evil agendas and an evil leader has awoken the gods of time and space but if you are playing the other game he awakens a demonic reality destroying deathly dimension beast

HG/SS: It’s like gen 2 with more legendaries

Black/White: Some vegans with a castle are protesting so you kidnap their king and beat up his dad for having a different opinion

Black 2/White 2: it’s like Black and White except with better cover art and the vegans are pirates now

X/Y: There was a war and a sad guy so go catch this deer

OR/AS: It’s like gen 3 but with more rayquaza and more VGC players in eternal pain

Sun/Moon: There are no more gyms only infestations here have a Pokémon and play exterminator for a whole game while we handhold you for no reason

US/UM: It’s like gen 7 but with more abominations

LGP/LGE: It’s like gen one with more cute

Sword/Sheild: Your friend has depression and you have to continually beat up his mediocre team so you can stop the president from beating the champion before you do