Here are my tips to win each campaign: EASY is obviously easy to win, no tips required; MEDIUM I have found using "building" cards and reach 100 most effective to win, have all your tower building and wall building cards along with crystals and bricks card, no weapons card at all; HARD I have found max out trojan horse cards + add 8 weapons, weapons special, as you need to build up 20 weapons (but you already have enough bricks), the attack on castle bypassing wall is perfect for a 30HP castle... having said all this, you'll need to reset it until you start off with a trojan horse, an add weapon card, and relying on your opponent not to build the castle. Hope this helps