This happens if the game cannot find the OBB file. Double-check that the com.konami.ygodg folder is spelled correctly and placed strictly inside the Android/obb/ directory.
Modded apps can sometimes request excessive device permissions (like access to contacts or storage). Deny any permission that seems unnecessary for a card game. Final Thoughts Yu-gi-oh Duel Generation Mod Unlock All Cards -UPD-
A: No – official online servers were shut down in 2020. The mod is for offline campaign and deck building only. This happens if the game cannot find the OBB file
He entered the Ranked Arena. His opponent was "Rex_Apex," a top-ten player known for a brutal lockdown deck. Usually, Kaito would be dead by turn three. "Let’s see how you handle this," Kaito whispered. Deny any permission that seems unnecessary for a card game
You can still earn cards by winning duels against AI opponents in the offline campaign.