Aernas is the mortal world where the main events of Grand Chase take place in.
Aernas is divided into two major continents: Bermesiah and Ellia, each hosting a number of regions. Xenia is a floating archipelago, while île de Frost and Silver Land are islands located near the Ellia peninsula and Kanavan respectively. A portal leading from Trivia has also opened up in the uncharted lands of the Bermesiah region.
The world parallel to Aernas is the Underworld, the land where the dead reside. There are portals connecting Aernas to the demon dimension known as Elyos, maintained by a God that the people of the Holy Kingdom in Bermesiah worship. However, the barriers separating the three worlds have weakened and are weakening still due to the actions of Ashtaroth, leading to the opening of portals that connect the worlds together.
At the beginning of time, a time so long ago that it cannot be determined, the Creator had created deities, the ones who will be responsible for creation of the universe, and the demons, who will be responsible for destruction.
Sometime before Kounat was founded, the Gods descended to the Archimedia Continent of primitive Aernas. These Gods consisted of Ernasis, the Goddess of war and valor, Lisnar, the Goddess of love and spirits, and Amenias, the Goddess of intelligence and harmony.
At that time, primitive humans, and primitive dwarves and elves who just started the tribal society were living in Aernas. The three Godesses chose humans, the most valorious and creative of all, as the race whom they will perform creation of the industry together with. Working together, Deities and humans created various life forms and developed the civilization soon to be christened Kounat in the center region of Archimedia.
- The world was only named until after Zero's release, and was confirmed in the Naver Blog.
- Aernas is noted to have an unstable mana flow as compared to the Underworld.
- Aernas is named after the representative of the deities who came to the planet, Ernasis.
- There is a set with the same name of the world: "Aernas Set".