Biorhythm is an in-game mechanism present in the games Fire Emblem: Path of Radiance and Fire Emblem: Radiant Dawn that affects all characters on the battlefield. Depending on a character's Biorhythm status, they may receive a bonus or penalty to Hit, Avoid, Skill activation and chance of finding hidden items.
Biorhythm status is indicated by either the red or green arrow next to a character's portrait or the sine wave in the Relations/Biorhythm section of a character's status screen. The higher the indicator, the better the Biorhythm status. Conversely, the lower the indicator, the worse the Biorhythm status. The Biorhythm status changes as the chapter progresses.
Biorhythm status can also be affected by the Bliss and Sorrow chants that Herons can learn, as well as the Matrona staff; also, the skill Tempest doubles biorhythm effects, whereas the skill Serenity halves biorhythm effects.
Biorhythm was referenced as a mechanic in Fire Emblem Awakening for beast units in the form of a skill, either Odd Rhythm (for Manaketes) or Even Rhythm (for Taguels), in which the character would receive skill bonuses if the turn number was either an even number, or odd number depending on which skill they have.
Fire Emblem: Path of Radiance bonuses/penalties[]
- Best: +5 Hit, +5 Avoid
- Good: +5 Hit, +5 Avoid
- Normal: No effect
- Bad: -5 Hit, -5 Avoid
- Worst: -5 Hit, -5 Avoid
Fire Emblem: Radiant Dawn bonuses/penalties[]
- Best: +10 Hit, +10 Avoid, +10% Skill activation, +20% Chance of finding hidden items
- Good: +5 Hit, +5 Avoid, +5% Skill activation, +10% Chance of finding hidden items
- Normal: No effect
- Bad: -5 Hit, -5 Avoid, -5% Skill activation, -10% Chance of finding hidden items
- Worst: -10 Hit, -10 Avoid, -10% Skill activation, -20% Chance of finding hidden items