How to deal with multiple KCs? e.g. I play two KCs and another Action card. Do I x6 everything written on it (including coins and buys) on the Action card? I read previous treads but still not very sure on this. Thanks
That "x6" makes me think you're playing incorrectly KC *and* Throne Room. You don't multiply "everything written on it (including coins and buys)", but play the card that many times. With basic cards like Village, Smithy or Market you won't notice the difference; but with something like Vault (+2 cards, you may discard cards for 1$ each) you do it twice (or thrice or whatever): +2 cards, discard, +2 cards, discard. NOT +4 cards, discard cards for 2$ each or any variant.