Terra's adventure in the Land of Departure is the same as that of Ventus' and Aqua's. The only main difference between their starting battles is how they are played out. While Terra and Aqua are tested in their Mark of Mastery exam, the Orbs of light summoned by Eraqus are unexpectedly given darkness. Your mission: to defeat them.
This battle serves as the player's test of applying all they have learned up until now. The Orbs are fast, but don't hit very hard. Ventus and Aqua will do the majority of the fighting, so instead of going after their targets, have Terra attack any Orbs that cross his path. His attacks are powerful but slow, so don't expect a full three-hit combo to connect, since the Orbs will dash away at warp speed if in danger. The Orbs can attack from all sides, but the damage they do is mediocre, so unless the player does absolutely nothing, they should win with ease. Terra receives his signature Command Style after this battle, where the Command Style mechanic is introduced and explained.
After a few cutscenes, Terra will leave the world and you'll be able to move on to your next.
After completing Terra's first world, Enchanted Dominion, the player can return to The Land of Departure to claim four treasure chests: a Soothing Crystal can be found to the left of the Summit, a Hi-Potion can be found to the left of the lower area of the Mountain Trail, Stop can also be found in the lower area, and a Pulsing Crystal can be found to the right of the upper area. Events in the story may cause the Land to be inaccessible for a time, so it is highly recommended that the player claim the chests immediately after completing the Enchanted Dominion, to avoid hassle.