|Effects||Grants the user increased Strength and Magic when the user is deployed on maps without sunlight and increased Defense and Resistance when the user is deployed in sunny outdoor maps.|
|Notes||Personal skill of Constance|
Circadian rhythms are physical, mental, and behavioral changes that follow a daily cycle. They respond primarily to light and darkness in an organism's environment.
- Circadian Beat appears to be a fusion of the skills Elbow Room and Natural Cover from Fire Emblem Fates, in that offensive and defensive stats are boosted depending on a unit's surroundings, though the trigger here is sunlight rather than terrain.
- Despite what the cutscene in Chapter 3 of Cindered Shadows may imply, hiding in treelines from the sun does not trigger Circadian Beat in sunny maps.
- Oath of the Dagger and Conclusion of the Crossing Roads, which share the same map, are the only maps in the game which have both indoor and outdoor sections. They are all considered "indoor" by this skill.