To unlock the Challenge level in Geometry Dash, the following steps are needed:
- Collect at least 200 diamonds in the game.
- Go to the Vault of Secrets in the main menu.
- Type the code "The Challenge" in the code redemption box within the Vault of Secrets.
- Once the code is accepted and the diamond requirement is met, the Challenge level will be unlocked and accessible from the vault menu.
- After beating The Challenge, additional surprises in the game can be unlocked.
Note that in some cases, players have reported bugs where The Challenge does not unlock even after meeting requirements, but generally, the above steps are the way to access it.
