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I was walking around in the moutains the other day when BAM !!! a shiny Sneasle (hope I spelt it right) popped up but damn it this one was so hard to catch I used up all my pokeballs from the Pokeball, Greatball, Ultraball and even my Duskball which I had about 20 of and yet it would not even get captured even with it's health down .... why are they so hard to catch