Pirate Archer is a great card to use with water team. It cost just 2 mana to use this card at battles in exchange this card will help you to destroy opponent's monsters easily with blast ability. Best advantage of this card is the blast ability. With blast ability he can attacks 2-3 monsters at the same round which is great at destroying opponent's shield. Most people use this card with Selenia Sky which is a clever choice. Also it will cost you less amount to level up this card because it's a cheap reward card. Because season ending is getting closer you can wait and buy this card at cheaper prices.