The In-Game Wallet is your default wallet in your GameBeef account.
All of your Play-to-Earn Rewards, Won Bets and Competition Prizes will be stored here indefinitely.
Whenever making deposits from your Phantom (global) wallet, the in-game wallet will receive the funds and you will be able to use them on the platform as you wish, this means you can:
For more details, you can click on the Wallet icon in the main menu:
You can also click on the button with the opposite arrows to see your actual cryptocurrency balance.