Saint-Croix Forest is a natural training facility meant to test bracers on their athletic and survival skills. As the name implies, it is a forest where bracers will go to learn basic or advanced survival skills such as hunting, fishing or camping and where they can learn about healing herbs and poisonous plants. It is also home to a variety of monsters, so bracers can go there for training.
Saint-Croix Forest is also the second stage of Estelle Bright's and Anelace Elfead's final test, where Estelle and Anelace woke up in the forest (after having been knocked out by jaegars) and had to find their out of the forest, while trying to their combat gear that was removed while they were unconscious. At the edge of the forest, Estelle and Anelace encounter and defeat the female jaegar who captured them and she tells them to head to Grimsel Fortress where they have imprisoned the captured Kurt Nardin.