Epic Heroes is an online, server-side game. The server validates your currency. Any local "hack" that changes your Diamond count will likely trigger an automated permanent ban.
Most "Cheat APKs" for Android are wrappers for malware, spyware, or "human verification" scams designed to steal personal data or serve aggressive ads. Epic Heroes Android Cheats
Instead of risky cheats, use these community-driven tools to optimize your account: Epic Heroes is an online, server-side game