His second ability, Cheer, triggers whenever one or more creatures you control with a counter on them deal combat damage to a player
From your 3rd win onwards, you'll receive an increasing number of gems and Arena Final Fantasy boosters per win
Instead of cards that generate immediate value on their own, exponential value tends to do a lot more work here
It is far better for the more aggressive player and blue is not the most aggressive colour
Cards like Delores Madrigal and Julieta both are strong draw cards that can be played to build up resources in your hand while also getting characters into play
For example, if you want to cast Fireball for 3 damage while a Thalia, Guardian of Thraben is on the board, you have to pay 1 extra mana in addition to the normal cost