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When I was little (about 8-9 years ago), I watched an animated series whose name I can't remember, but I really liked the series so I want help to find its name. I can't remember the media source, but I watched them in Bulgarian.
In the series there was a purple boy (he wore loose purple trousers and had purple hair), I think his name was Strack or something like that, and there were some kind of monsters, that could be summoned by gems. There were other kids too and they were Strack's friends and еach one had a gem. I remember a big forest too.
It's not much information, but I hope it helps.