I was doing excavation site the Mineral site when I encountered a wild beldum, so I attempted to catch it only thing is I can't use false swipe without it taking itself out so I thought I'd use it's take down against it and let it lower it's own health except it didn't. no matter how many times beldam used take down its health never went down so I tested something. I used my weavile's false swipe and then beldum used take down it suffered recoil but no self damage. further more I threw ultra balls, great balls and pokeballs and none of them worked I was unable to catch the beldum I didn't run out of pokeballs it became apparent to me that it may be a bug.