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The Impregnable Fortress (Silver Snow)

From Fire Emblem Wiki, your source on Fire Emblem information. By fans, for fans.
The Impregnable Fortress

Cg fe16 opening 04.png
Mural used to introduce The Impregnable Fortress.

Previous chapter(s)

The Rose-Colored River

Next chapter(s)

The Chaos of War

Will death's scythe claim you... Or will I fall to that sword of yours...
— Death Knight

The Impregnable Fortress (Japanese: 鉄壁の要塞 Impregnable Fortress) is the seventeenth chapter of Fire Emblem: Three Houses on the Silver Snow route.


Main article: The Impregnable Fortress (Silver Snow)/Script

A Church soldier reports that Imperial, Kingdom, and Alliance forces had a massive battle at Gronder Field; Edelgard was badly injured and forced to retreat to Enbarr, Dimitri is dead, and Claude is missing. Despite his shock at these events, Seteth elects to take advantage of the damage done to the Imperial army to launch the Resistance's own invasion of Adrestia, using Fort Merceus as a foothold. Flayn also notes that Faerghus and Leicester are likely in disarray due to the loss of their leaders, and Seteth notes that Byleth will have to unite them under one union. Afterwards, Byleth wanders outside the monastery and seemingly encounters Dimitri, who laments his own actions up to this point. Seteth appears, berates Byleth for falling asleep in such a place, and denies seeing Dimitri.

At the end of the month, the Resistance infiltrates Fort Merceus using stolen Imperial uniforms. They conquer the fortress and defeat the fortress' commander, the Death Knight, who beckons them to pursue him as he escapes. He warns the Resistance to flee before they are all killed and escapes just as modern-day ballistic missiles obliterate Fort Merceus. The shocked and demoralized Resistance forces retreat to Myrddin, where Byleth and Seteth decide to infiltrate Enbarr and gamble everything on an all-or-nothing attack on the palace.

Calendar - Harpstring Moon

Harpstring Moon
Monday Tuesday Wednesday Thursday Friday Saturday Sunday
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12 13 14 15 16 17
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19 20 21
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22 23 24
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25 26 27
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28 29 30
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Note that the Great Tree Moon was skipped between the previous chapter and this one, and events that take place during that month, such as Ferdinand's birthday, are not interacted with.

Character data

New units


Available characters
Byleth f 02 ​Ferdinand 02 ​Linhardt 02 ​Caspar 02 ​Bernadetta 02 ​Dorothea 02 ​Petra 02 ​Felix 02 ​Sylvain 02 ​Mercedes 02 ​Annette 02 ​Ingrid 02 ​Raphael 02 ​Ignatz 02 ​Lysithea 02 ​Marianne 02 ​Leonie 02 ​Yuri 02 ​Balthus 02 ​Constance 03 ​Hapi 02 ​Anna ​Shamir ​Flayn ​Hanneman ​Manuela ​Alois ​Seteth ​Catherine ​Cyril 02 ​Hilda 02 ​Ashe 02 ​Lorenz 02 ​

Item data

Name Obtainment Method
Is ns01 staff.png Magic Staff Tournament prize
Is ns01 bullion.png 3,000G Quest reward: Supply Run
Is ns01 gift.png Legends of Chivalry Quest reward: Worried Warrior
Is ns01 bait.png Herring Bait (×2) Quest reward: Worried Warrior
Is ns01 bait.png Earthworm (×5) Quest reward: Worried Warrior
Is ns01 shield.png Aurora Shield Northeastern chest in Taking Fort Merceus
Is ns01 stat booster.png Speedwing Southeastern chest in Taking Fort Merceus
Is ns01 seal.png Dark Seal Dropped by the Death Knight in Taking Fort Merceus
Is ns01 axe.png Brave Axe Dropped by enemy Warrior in Taking Fort Merceus
Is ns01 ring.png Evasion Ring Dropped by enemy Swordmaster in Taking Fort Merceus


Main article: The Impregnable Fortress (Silver Snow)/Taking Fort Merceus

This is the last month the paralogue Foreign Land and Sky can be done, so get working on it if it's available and hasn't been done.


  • The story event "The Death Knight" has a trigger to add Caspar and Linhardt next to the Death Knight if they are unrecruited, similar to how the Azure Moon and Verdant Wind counterpart of this event works. As this scenario is impossible without hacking, this variation of the event goes unused.[1]
  • In the cutscene at the end of this chapter, Byleth's troops wear armor with a unique black and pink palette only seen in this cutsecne that is not explicitly affiliated with any of the factions. This is possibly due to the fact that this scene is present in both the Silver Snow and Verdant Wind routes.
    • At the end of the same cutscene, there is an animation error where Byleth's eyes are their original blue color instead of green.

Etymology and other languages

Names, etymology, and in other regions
Language Name Definition, etymology, and notes

The Impregnable Fortress




Impregnable Fortress


La fortaleza inexpugnable

The impregnable fortress


La forteresse inexpugnable

The impregnable fortress


Die uneinnehmbare Festung

The impregnable Fortress


La fortezza inespugnabile

The impregnable fortress


철벽의 요새

Iron-walled fortress

Simplified Chinese


Impenetrable fortress; lit. "fortress with walls like iron"

Traditional Chinese


Impenetrable fortress; lit. "fortress with walls like iron"


This section has been marked as a stub. Please help improve the page by adding information.


  1. Silver Snow. Event 28 - The Death Knight,, Retrieved: July 4, 2020
← The Rose-Colored River • The Impregnable Fortress • The Chaos of War →
Fire Emblem: Three Houses
Playable characters Black Eagles BernadettaCasparDorotheaEdelgardFerdinandHubertLinhardtPetra
Blue Lions AnnetteAsheDedueDimitriFelixIngridMercedesSylvain
Golden Deer ClaudeHildaIgnatzLeonieLorenzLysitheaMarianneRaphael
Other AloisAnnaDLCBylethCatherineCyrilFlaynGilbertHannemanJeritzaManuelaSetethShamir
Ashen WolvesDLC BalthusConstanceHapiYuri
Non-playable characters AbysskeeperDLCDuke AegirFlecheGatekeeperDuke GerthIonius IXJeraltJudithLadislavaNaderRandolphRheaRodrigueSothis
Bosses AcheronAelfricDLCAloisLord ArundelBiasBlaiddydCasparCatherineCharonChilonClaudeCorneliaDaphnelDedueDeath KnightDimitriDominicBaron DominicEdelgardFelixFerdinandFlame EmperorFlaynFraldariusGautierGloucesterGonerilGwendalHubertIngridThe Immaculate OneThe ImmovableJudithKostasKronyaLadislavaLamineLinhardtLonatoLorenzMercedesMetodeyMiklanMysonNaderNemesisBaron OchsDLCOdessePallardóPittacusRandolphRheaRieganRodrigueSetethShamirSolonSylvainThalesWandering BeastThe Wind Caller
Background characters Lord ArundelCount BergliezCorneliaMargrave GautierGlennCount GloucesterCount HevringHolstLambertMonicaPatriciaRufusSeirosSitriTomasTianaCount Varley
Personal weapons and regalia Aegis ShieldAreadbharAsclepiusAthameAxe of UkonvasaraAymrBlutgangCaduceus StaffCirce StaffCrusherFailnaughtFetters of DromiFreikugelThe InexhaustibleLance of RuinLúinOchain ShieldRafail GemScythe of SarielSeiros ShieldSpear of AssalSword of BegaltaSword of MoraltaSword of SeirosSword of the CreatorTathlum BowThunderbrandThyrsusVajra-Mushti
Chapters Part I
White Clouds
P: An Inevitable Encounter • 1: Three Houses • 2: Familiar Scenery • 3: Mutiny in the Mist • 4: The Goddess's Rite of Rebirth • 5: Tower of Black Winds • 6: Rumors of a Reaper • 7: Field of the Eagle and Lion • 8: The Flame in the Darkness • 9: The Cause of Sorrow • 10: Where the Goddess Dwells • 11: Throne of Knowledge • 12: To War Black Eagles, if Byleth sides against EdelgardBlue LionsGolden Deer / Outset of a Power Struggle Black Eagles, if Byleth sides with Edelgard
Part II Silver Snow
Silver Snow
13: Reunion at Dawn • 14: A King Without a Kingdom • 15: Valley of Torment • 16: The Rose-Colored River • 17: The Impregnable Fortress • 18: The Chaos of War • 19: Conclusion of the Crossing Roads • 20: The City Without Light • 21: Following a Dream
Azure Moon
Azure Moon
13: Reunion at Dawn • 14: The Delusional Prince • 15: Valley of Torment • 16: The Rose-Colored River • 17: Blood of the Eagle and Lion • 18: The King's Triumphant Return • 19: The Golden Deer's Plea • 20: The Impregnable Fortress • 21: Our Chosen Paths • 22: Oath of the Dagger
Verdant Wind
Verdant Wind
13: Reunion at Dawn • 14: The Alliance Leader's Ambitions • 15: Valley of Torment • 16: The Rose-Colored River • 17: Blood of the Eagle and Lion • 18: The Golden Scheme • 19: The Chaos of War • 20: Conclusion of the Crossing Roads • 21: The City Without Light • 22: Fódlan's New Dawn
Crimson Flower
Crimson Flower
13: Beyond Escape • 14: The Master Tactician • 15: Tempest of Swords and Shields • 16: Lady of Deceit • 17: Field of Revenge • 18: To the End of a Dream
Paralogues Paralogues Part I Black Market SchemeDLCA Cursed RelicDLCDeath TollDividing the World Black Eagles, if Byleth sides against EdelgardBlue LionsGolden DeerFalling Short of HeavenThe ForgottenLand of the Golden DeerAn Ocean ViewOil and WaterRumored NuptialsThe Secret MerchantDLC Blue LionsGolden DeerSword and Shield of SeirosTales of the Red CanyonTrue ChivalryWar for the Weak Blue Lions
Part II Darkness Beneath the Earth Crimson FlowerDividing the World Silver SnowAzure MoonVerdant WindEternal Guardian Silver SnowAzure MoonVerdant WindThe Face Beneath Silver SnowAzure MoonVerdant WindForeign Land and SkyForgotten HeroInsurmountable Crimson FlowerLegend of the LakeRetribution Silver SnowAzure MoonVerdant WindThe Secret MerchantDLC Crimson FlowerThe Silver Maiden Azure MoonThe Sleeping Sand Legend Verdant WindWeathervanes of Fódlan Azure Moon
Cindered Shadows
Cindered Shadows
1: The Fourth House • 2: What Lies Beneath • 3: The Rite of Rising • 4: Danger in the Dark • 5: Betrayal • 6: Return to Me • 7: Wolf Pack
Locations FódlanAdrestiaFaerghusGarreg Mach Monastery (Abyss) • LeicesterAlmyraBrigidDagdaSrengZahras
Groups, objects and concepts 10 ElitesAshen WolvesBlack Eagles (Black Eagle Strike Force) • Blue LionsChildren of the GoddessChurch of Seiros (Knights of Seiros) • Crests (Crest Stone) • Divine PulseGolden DeerHeroes' RelicsInsurrection of the SevenMonstersThose who slither in the darkTragedy of DuscurWar of Heroes
Lists AbilitiesChaptersCharactersClasses (Class change) • Hidden treasureItems (Monastery items) • QuestsScriptsSupportsWeapons
Related topics Music LibraryName chart • Other games (Warriors: Three Hopes) • Pre-release informationUnused contentDownloadable contentClass mastery