Wild Swellow
When you get surf, go back to rustburo and keep going up you should reach some water if you keep surfing eventually you'll reach a place where there is some trees a little cliff with a sand slope if you keep going up you should encounter a trainer defeat him (he has a lvl 27 hariyama)then if you go up there is a grassy patch you can catch here Wild Swellow, Jigglypuff, Taillow and some more I forgot but most of them are arond 25-28 so happy catching.
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