When activating spells or using secondary weapons, you may trigger panic or surprise to a group of enemies. Surprised enemies are immobilized and defenses lowered while panicked enemies have their abilities weakened. Fear immobilizes affected units, preventing them from taking action in a short span of time.
Defeating enemy commanders also triggers negative emotions to enemies, giving you an upper hand for a few moments. Emotions doesn’t last long so make sure to act quickly before enemies recover. Your allies can also be affected by emotions, lowering their efficiency. As such, it is recommended to avoid combat until they calmed down.
Aside from emotions, you also have to look out out for other status effects such as burn, impair, and shock. Each of them have different effects which can help turn the tide of battle.