If u are buying cards, i suggest buy alpha or alpha gold or beta gold edition cards. When u use these types u get dec bonus in a huge amount actually. There are different types of attacks, melee, ranged, magic, some with sneak ability. If u use melee attack at the and they wont be able to attack and u will loose. Learn a little about the attact types, monster ability, summoner ability and then u will find it easy and interesting to play. When i first started i made these mistakes too.... And i kept loosing for choosing the wrong cards..... Good luck