Form a party of five officers and work your way through stages of increasing difficulty. Each stage is made up of multiple battlefields that you must explore in order to find the hidden escape point while defeating enemies and gathering items along the way.
Using the escape point, you can proceed to the next battlefield, and once all of the battlefields have been cleared, you will have completed that stage. One by one, the stages are cleared until you can reach the powerful enemy that awaits you in the world's depths.

*Japanese screenshots are shown.
At the start of each battle, the map is covered in a layer of "miasma" that will gradually recede as you explore the battlefield. Through the activation of the Dragon Portals throughout the stage, you can unlock various effects such as ones that weaken the enemy or recover your party's Life Gauge. One of the Dragon Portals will also contain an escape point that lets you clear the battlefield.
You are also able to switch between three different battle formations in order to gain the upper hand in battle. The mode can be played online as well as with two player co-op play via split screen. Both players can select a character to play as from the party members.