@cem0f0r
5/7
To play a card, you simply drag it towards the opponent you intend to attack. (Some cards are meant to be used on you, so simply drag it to your ship to use it.)
When a user exhaust his/her attack point, you proceed to end the turn and let your opponent play it's turn.
PS: When faced with multiple enemies, try killing the one with lower health so as to avoid continuous damage from it.