Dragon Ball
Gundam
rest can vary. but those two pretty much are a lock. Astro Boy is iconic as you can get and their version of our Mickey Mouse, but i don't think i'd put it on something devoted to anime either because that evolved well past him. One Piece has been around for so long carrying so much influence on the shounen genre that it really is DB 2.0, so it probably deserves the spot. Pokemon also is a very strong contender here as its influence, along with DBZ, made the US market, was a big hit into games + anime combinations, and was the series out there, spawning a ton of spinoffs and style changes within anime.
so yeah, last two = One Piece and Pokemon. Pokemon's influence is less to do with the anime genre within itself and more to do with spreading it across people of all ages better than anything else did on a global level.
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The King Wang.
Listen up Urinal Cake. I already have something that tells me if I'm too drunk when I pee on it: My friends. - Colbert.