i think you should have an option that allows players to pay for packs with different forms of payment like dps, coins and card pieces; like tyrant does with their packs. I also think their should be daily rewards for free so more people will continue to comeback to play this. Lastly players of higher levels should be able to gain more energy to play longer and reduce the energy required to play some of these challenges.
im sorry but this game has alot of balancing issues i wish i could have picked vampires at the begging cause they are best cards right now make new cards please
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