Earth Mode is one of the difficulty settings in the Star Ocean series. Earth mode is always the easiest difficulty, with the weakest enemies and weak AI.
Earth Mode is the default difficulty, and the only one available to begin with.
Earth mode is the easiest difficulty, but not the default one. Compared to Galaxy Mode, the default difficulty, enemies have 0.7x HP and MP for an easier challenge. However, it is impossible to obtain Battle Trophies while playing on Earth Mode. While in the Maze of Tribulations the game is set to Galaxy Mode but Battle Trophies are still locked.