There's an official software to play online, where you also need to buy packs with random virtual cards to play. But there's also non-official softwares where y

There's an official software to play online, where you also need to buy packs with random virtual cards to play. But there's also non-official softwares where you can use any card. How to maintain the balance? This is the core game's responsibility. To create cards and mechanics which aren't just pay to win.