Which generation made the most important additions to Pokemon?

Every generation of Pokemon has added something new to the games that has made Pokemon what it is today. But which generation added the best or most important features? What is the generation that made the biggest impact in revolutionizing Pokemon from what it was in Gen 1? The addition of breeding? The physical/special move split? The addition of natures and abilities? The addition of Hyper-training to make any Pokemon competitively viable without having to spend time breeding for IVs? The addition of shiny Pokemon if you like shinies? Which generation would you say made the BIGGEST impact on what Pokemon is today? (Obviously I left out Gen 1 because obviously the creation of Pokemon is the most important lol)

Edit: Here's some of what I missed from the poll that others have mentioned:

Gen 2:

  • Held Items

  • Special Attack and Defense split

  • Second playable (female) character

  • Separate pockets in the bag

  • Apricorn balls

  • Dark and Steel types

  • Mystery Gift

  • Genders

  • Egg moves

  • Berries

  • Friendship

  • Pokerus

  • Weather

  • Battle Tower

Gen 3

  • Updated PC Box system format

  • Modern IV and EV format

  • Double Battles

  • Running shoes

  • Move Reminder/Deleter

  • Move previews when leveling up

  • New berry system

  • New pokeballs

Gen4

  • Wi-Fi connectivity

  • Gender appearance differences

Gen 5

  • Auto reusing repels

  • Hidden abilities

Gen 6

  • Player customization

  • Fairy type

  • New EXP Share to cut down on grinding

View Poll