Luck (幸運 Kōun) is a core character statistic in the Fire Emblem series that serves a variety of functions. As with the other core stats, it has a chance of increasing each time a character levels up.

Overview

Luck is a stat that varies in effect, but is best described as a character's ability to achieve unexpectedly favorable results. Luck does impact Hit Rate and Avoid, but to a lesser extent compared to Dexterity/Skill. Its most notable effect in all games is in the hidden Critical Evade stat, which gives luckier characters a chance to outright avoid critical hits against them. Luck is also associated with Skills as one of the more commonly use stats when determining activation percentages of skills such as Miracle and Armsthrift.

Game-specific Luck Effects

Fire Emblem: Shadow Dragon and the Blade of Light

• Luck does not affect Hit Rate at all in this title.
• Luck only boosts your Avoid against Magical attacks specifically (Luck)%.
• There is also no Critical evade stat in this title, therefore Luck does not boost it.
• It does boost the rates of Critical hits however ([Skill + Luck]/4)%.

Fire Emblem Gaiden

• Luck remains very similar to Shadow Dragon.
• Luck's boost to Magical Avoid is now (Luck/2)%.

Fire Emblem: Mystery of the Emblem

• Luck does not affect hit rates and no longer boosts critical hit rates.
• Luck's bonus to Avoid is ([Skill + Luck]/2)%.
• Luck's bonus to Critical Evade is (Luck)%.

Fire Emblem: Genealogy of the Holy War

• Luck affects purely Avoid when it comes to core stats ([Attack speed × 2] + Luck)%.
• Ulir blood gives a 30% boost to luck growth and Baldr and Bragi blood give a 10% boost to luck growth.

Fire Emblem: Thracia 776

• Luck now affects Hit Rate ([Skill x 2] + [Luck])%.
• Luck's bonus to Avoid is ([Attack speed × 2] + Luck)%.
• Luck's bonus to Critical Evade is (Luck/2)%.
• Luck also for the first time has an effect on a unit Skill, in this case Miracle.

Fire Emblem: The Binding Blade

• Luck affects Hit Rate rate in this title, granting to bonus of [(Skill x 2] + [Luck/2])%.
• Luck's bonus to Avoid is ([Attack speed × 2] + Luck)%.
• Luck's bonus to Critical Evade is (Luck)%.

Fire Emblem: The Blazing Blade

• Luck remains entirely unchanged from The Binding Blade. However the formulas for Hit Rate, Avoid, Critical Hits and Critical Evades do change due to other factors.

Fire Emblem: The Sacred Stones

• Luck once again stays unchanged from the prior two Game Boy Advance titles, but like before the formulas for Hit Rate, Avoid, Critical Hits and Critical Evades do change due to other factors.

Fire Emblem: Path of Radiance

• Luck affects Hit Rate rate in this title, granting to bonus of ([Skill x 2] + Luck)%.
• Luck's bonus to Avoid is ([Attack Speed x 2] + (Luck)%.
• Luck's bonus to Critical Evade is (Luck)%.
• Luck also once again affects a single Skill in the Titles: Miracle.

Fire Emblem: Radiant Dawn

• Luck remains exactly the same as it was in Path of Radiance, including effecting only the Miracle Skill. However the formulas for Hit Rate, Avoid, Critical Hits and Critical Evades do change due to other factors.

Fire Emblem: Shadow Dragon

• Luck affects Hit Rate rate in this title, granting to bonus of (Skill + [Luck/2])%.
• Luck's bonus to Avoid is (Attack Speed + [Luck/2])%.
• Luck's bonus to Critical Evade is (Luck)%.

Fire Emblem: New Mystery of the Emblem

• Luck affects Hit Rate and Critical Evade identically to Shadow Dragon.
• Luck's bonus to Avoid is (Speed + [Luck/2])%.

Fire Emblem Awakening

• Luck affects Hit Rate similarly to the Nintendo DS titles, ([Skill x 1.5] + [Luck/2]).
• Luck's bonus to Avoid is ([Speed x 1.5] + [Luck/2]).
• Luck's bonus to Critical Evade is (Luck)%.
• Luck also now affects multiple skills within the game: Despoil, Armsthrift, and Miracle.

Fire Emblem Fates

• Luck affects Hit Rate differently from previous titles, as Fates introduced two formulas for hit rates: One for Weapons and one for Staves, with Luck only affecting the Hit Rate of the former ([Skill x 1.5 + [Luck/2]).
• Luck's bonus to Avoid is ([Speed x 1.5 + [Luck/2]).
• Luck's bonus to Critical Evade is (Luck/2)%.
• Luck is used by a handful of Skills in Fates: Dragon Ward, Salvage Blow, Miracle, Profiteer, Good Fortune, andWitch's Brew. As well as a few Personal Skills: Prayer of Bonds, Collector, Goody Basket, and Make a Killing.

Fire Emblem Echoes: Shadows of Valentia

• Shadows of Valentia once again brings back the split between Magical Attacks and Physical Attack, with Luck only boosting your Hit Rate with Magical Attacks ([Skill + Luck]/2)%.
• Luck's Bonus to Critical Hit Rate is ([Skill + Luck)/2]%.
• Luck's bonus to Magical Avoid is ([Speed + Luck]/2)%.
• Luck's bonus to Critical Evade is (Luck/2)%.
• Luck once again affects a single Skill in this title: Miracle.

Fire Emblem: Three Houses

• Three Houses keeps the split between Magical Attacks and Physical Attacks, with luck only boosting your Hit Rate with Magical Attacks ([Dexterity + Luck]/2)%.
• Luck's bonus to Magical Avoid is ([Speed + Luck]/2)%.
• Luck's bonus to Critical Evade is (Luck)%.
• Luck is also used once again by a single skill in this title: Miracle. It does however affect one Personal Skill as well: Goody Basket.

Fire Emblem Engage

• Luck no longer provides a bonus to Critical Hit Rate in this title.
• Engage splits Hit Rate into three different types depending on the whether a Weapon, Staff, or Cannonball is being used, with Luck effecting all three in terms or Hit Rate and Avoid.
• Luck's bonus to Weapon Hit Rate is ([Dexterity x 2] + [Luck/2])%.
• Luck's bonus to Cannonball Hit Rate is ([Strength + Dexterity + Build] + (Luck/2)]%.
• Luck's bonus to Weapon Avoid is ([Speed x 2] + [Luck/2])%.
• Luck's bonus to Staff Avoid is ([Resistance x 1.5] + ([Luck/2])%.
• Luck's bonus to Critical Avoid is (Luck)%.
• Luck is used by a handful of Skills in Engage: Divine Pulse, Lost & Found, Windsweep, Miracle. As well as one Personal Skill: Seconds?

Trivia

• In Fire Emblem Fates, Arthur has the lowest Luck growth out of any character in the entire game at 10%. It is further lowered to 5% in one of the potential promotions of his default class, Berserker. This is a reference to his character having notoriously bad luck in the story and in all of his supports.
• In a vein similar to Arthur, Dice is a character who, narrative-wise, has notoriously bad luck, though this does not reflect as sorely as Arthur in gameplay. In Archanea Saga, Dice has a Luck growth rate of 60%, and a growth rate of 40% in New Mystery of the Emblem. He does, however, come equipped with a Devil Axe, which has a chance of dealing damage to its wielder with every attack based on a calculation where the lower the unit's Luck, the more likely a backfire is to occur.