I accidently battled a wild Pokemon when there was a Pokemon that I was still EV training in my party. I don't want to reset all of its stats because I already maxed out Hp. Can I get EV reducing berries in Pokemon Y?
If you scroll down it will tell you the EV reducing berries. It will also tell you that you can only get them via mutation. If you scroll down even further, it will show you how to get them from mutation.