Today I discovered an unintended bug where a completely won position was lost becasue of priority being automatically passed while I was still able to take game actions.

Here is an example board state:

Underworld Breach is played on my side, I have a lotus petal in play and 7 cards in my graveyard, and am tapped out of lands; the cards in my graveyard are 6 lands and a brain freeze.

As the game works currently, the priority mechanism looks at my boardstate, decides that I cannot cast any spells by cracking my lotus petal to generate one mana, and passes priority. This means that i cannot ***** petal --> replay petal --> ***** petal --> cast brain freeze, unless I hold full control.

Unfortunately, I did not know this unintended mechanic existed, and lost 2 cube games this way, causing me to lose 2 games which I had won (Breach, petal, brain freeze, with enough cards in yard to loop). I understand that holding full control would stop this occurance, but believe that the system should be smart enough to not pass priority with a breach resolved and a spell I can cast. This cost me real money in the form of gems which I cannot recover.