So i played a game in the Arena, Gold league. It went on just fine.
I lost that game, fair and square. I went back to the arena menu.
Here's where it gets weird.
When the menu loaded, it's going back to the arena tutorial screen (the one with arrows and texts all over). No screenie because i was waiting to play Gold, and reflexively click on it after it loaded (i still see the arrows for a split second, though)
I fought the same guy again. But this game was different. He started with 3 cards, my game is normal. I played as usual, and he didn't play any card. Also, everytime he ended his turn, he discarded one card, as if he had maximum cards on hand already. Still no screeny because a screeny can't really confirm this.
Then i won the game, EM. And the spin screen goes like this:
This screeny is the only one can be truly confirmed as a bug. It's spinning, and on the third spin, i can hear the sound of 2 cards matching, and the sound of winning the card. Haven't check the card, though.
And when i got back to the main arena screen, everything went back to normal.
I'll check more details on this, and also the won card. If the bug is bigger, i'll report back here.
EDIT: so it seems no strange card won, as they are all normal. Maybe this is just a graphical glitch, seeing that when i fought him the second time, i got Discord early (and possibly quanta locking him to play cards)
And it seems like the Arena menu returning to tutorial screen is already confirmed, but they might be related.
EDIT2: It happen again, but this time it's the arena tutorial screen.
This part has already been confirmed IIRC.