Just want to know if your allowed to take notes during games? Like say I used Bitter Rivals, could I write down what my opponent had in their hand? If I add a card to my momentum can I write the order I put them in? Etc? Of course you have to be kind of quick about it and not slow the game/stall the game out because of it or anything, but can you quickly jot down some notes during a game?

Long as you do it in a timely manner.