While officially shut down its servers on September 30, 2020, the single-player campaign remains playable for those who have the game installed. Because the in-game store is also closed, players often look for "All Cards Unlocked" mods (usually in APK form for Android) to access the game's full library of over 7,000 cards. The "Best" Way to Unlock All Cards
That being said, here are some general steps and considerations for modding Yu-Gi-Oh! Duel Generation: yugioh duel generation mod unlock all cards best