The player will be prompted a couple of times to ensure that they want to begin in Sandbox mode, as it will not allow them to unlock anything new or gain any Achievements. Select the orange ship in the lower left, and choose Play Sandbox Mode. Sandbox Mode is accessed at the beginning of the game, after choosing a save game slot. Other game modes include Adventure Mode and the announced, but unreleased 'Survival Mode.'
Sandbox Mode is one of the base game modes in Lego Worlds, centered around building and exploring.