Hello Ladies and Gent's!
I started playing on PRO on Yellow somewhere at the start of August and sometime after battling Brock i noticed that i had a Master Ball in my inventory. I think i didn't even travel through Mt. Moon at the time so I didn't have the possibility to use dig. I caught a Squirtle ( the Blastoise i use now ) in Alabastia with it to confirm if it is an actual Master Ball and not just an appearance bug or something. I wasn't sure at first if this is even a bug at all because there was the anniversary going on - but after some conversations with people ingame and on Discord I got convinced to post this here online. I sadly don't have screens of it so my story is all i can tell you as proof.
With best regards
Rudeus
