User Summary Cardian is a tower defense game in the guise of a collectible card game. You first build your deck from the starter packs and booster cards screens, then battle commences and a selection of your cards is drawn at random. You must defend your portal and launch an assault on the enemy portal using the cards drawn, some of which will summon troops, some will bring status effects into play and others will help you accumulate resources. If you succeed in defeating the enemy you gain a reward in gold, and more card packs can be bought.