solemnity
Right now there is a gamebreaking bug with solemnity/nine lives. I was playing my first ranked game of the season, after being reduced from platinum to gold (not flexing, just trying to provide as much information as possible)
In game 1, my opponent played solemnity, and then exiled my evolution sage with Ixalan's binding. My Evolution Sage had 2 +1/+1 counters on it, which triggered my ozolith. I surrendered with my ozolith trigger on the stack, going to game 2 boarding in return to nature.
Game 2, my opponent played nine lives early on, but for some reason, even though he had no creatures out and I had about 6, all with +1/+1 counters, I was unable to attack my opponent and put counters on nine lives. I should mention again, at this point there was NO SOLEMNITY ON THE BATTLEFIELD.
Basically, something is going wrong with solemnity leaving the battlefield when the game ends, and its effect is doing something with attackers and nine lives, breaking the game and making it unwinnable for the person facing the bug abuser.
In this case, i can be certain it was an abuser because they were playing things that made their enchantments/artifacts untouchable, like Destiny spinner, and something that gave solemnity shroud.
This bug is definitely going to be breaking ranked if it gets more prominent, and after my first game of the January season, I'm going to be avoiding ranked until either solemnity is banned or this bug gets fixed.