But you should pay extra attention to dice rolls when you have a monopoly card.
Monopoly: here's where keeping track of cards played becomes even more important. Catan is a near perfect information game - it is possible to know exactly what cards are out there, if not exactly who has got what - but in practice only real card-counting sharks can do this. But you should pay extra attention to dice rolls when you have a monopoly card. Alternatively, peek at the stacks of resource cards - if one is getting low, hit that. A sneaky trick is to trade away cards you plan to monopolize later in your turn. Most powerful in the end game, monopoly cards are probably more important to damage your opponents than they are to get you usable resources, so play them accordingly.