I made this thread to share funny glitches all around UR!
Play Bubblgm in your app on the phone (only tried on android, dunno if it works on apple) and be in-game. If u got Bublgmm, great! First press a card which does not have the rarity common. Press a Silver or Gold-card to see info. Then after, press on Bubblgm to see his stats, now he has turned into the rarity of previous.
Only works on him, mysterious!