I accidentally defeated Mewtwo in Pokemon Y..?

Question

I accidentally defeated him in the Unknown Dungeon, will he ever come back? I Meant to lower his health so I could catch him but it backfired and i'm wondering if it changed whether static Pokemon come back eventually after beiong defeated. Help?

Thanks

Answer 1

Mewtwo will return again available for you to battle once you defeat the Pokemon League again.

Hope I helped. :)
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