The Pokedex indicates that you can only get it in the National , with Sinnoh-Sound. I can't find it though! I checked trees, grass, and tall grass, but I CAN'T FIND IT! Please help me, I'm getting gray hairs.
You can't find cherubi through the sinnoh sound. you can get it by using headbutt on a specific tree http://www.serebii.net/heartgoldsoulsilver/headbutt.shtml
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