Most battles are initiated by coming in contact with a wild enemy. Multiple opponents can enlist themselves in a battle by either joining the battle during the transition screen or being called upon by another fellow opponent during the battle. Depending on which direction the enemy touched you, the enemy or a group of enemies may be awarded a free starting attack if they touch you on the side or from the back. The same principle applies to you; touching an enemy on the side or from the back will result in you getting a free starting attack on the enemy. Wild enemies appear randomly in different areas of the game, meaning it's possible to force the game to generate a new set of enemies (or no enemies at all!) simply by exiting and entering from the door or portal you came in. In some cases you can walk far away enough from an enemy spawn point that a new set of enemies will spawn, however this isn't recommended since you might unintentionally run into another set of enemies. Once touched by an enemy, the screen will tint red as a visual cue if the enemy will be rewarded with a free starting attack. Likewise, the screen will tint green if you are awarded a free starting attack. If you are significantly higher in level than the enemy you will instantly win against them and gain experience and items.
Once a battle is started, the enemies will be presented in randomly-ordered rows. The ally with the most speed will be selected first. Actions for each character to commit are presented in its menu. Upon selecting an action for one ally, another menu will appear with the actions possible with the next ally in your party. Generally six main options are provided in each character's menu, in addition to some character-exclusive actions: Bash, goods, auto fight, PSI, defend, and run away.
During a battle with a toxic enemy, your character may encounter a status ailment. Walking in the desert can also cause a status ailment (specifically, sunstroke). Status ailments are sicknesses that handicap an ally's ability to fight or maintain a constant HP. Common ailments cause your character's HP to slowly decrease while walking around or during battle.
Ailments can be healed, usually through a healer in the local hospital or by means of a medicine.