Mortal Shell 2: Great Martyr’s Blade Location Guide

The Great Martyr’s Blade is a two-handed greatsword in Mortal Shell 2, and it is sitting in a side dungeon you can reach early. The pickup is in Martyr’s Prison, on the northwestern side of the map beside the Citadel of Penance. That dungeon is not Martyr’s Tomb. If you walk into the Tomb, you are in the wrong building.

Quick answer: Open the inner gate in Martyr’s Prison, clear the room, then take the Great Martyr’s Blade from the stone altar.

Martyr’s Prison map location

Martyr’s Prison sits on the outer wall of the Citadel of Penance, in the Gloomshade Grove area. The nearest beacons people use as landmarks are Widow’s Overlook, Blackridge Pass, and Gloomshade Grove. Open your map and look northwest, next to the citadel, rather than deeper into the citadel interior.

In-game map with a circular cursor over clustered location markers — The map screen with the cursor moving across revealed beacons and dungeon markers. Image: Cold Symmetry

If Gloomshade Grove is already lit, you can skip the well and go straight west toward the citadel wall. The prison door is often tucked behind wooden boxes near a few miners. Do not keep following the Eredrim line into the citadel. That path shares some of the same countryside and then peels away from the weapon.

Merrick in Marrow Keep also sells a map that marks the Great Martyr’s Blade for 500 Coins. You do not need that map if you can already see Gloomshade Grove and the citadel wall.

Mother’s Breath and other path blockers

The short run from Widow’s Overlook cuts through Blackridge Hamlet. Corruption walls close that village until you have Mother’s Breath. You unlock Mother’s Breath at Marrow Keep after you turn in Over Eggs. Without it, the hamlet route stops at a sealed wall.

Blocker	What it stops
No Mother’s Breath	Corruption walls on the Blackridge Hamlet path stay sealed
Locked Citadel gate	The official door into the citadel side stays shut
Martyr’s Tomb	Wrong dungeon, no blade
Inner prison gate still down	You cannot reach the altar room

If you arrive at the citadel gate and it wants a lever you do not have, face the gate and move right. There is a gap you can squeeze through to the far side. The Blood-Cursed Lithopod near Gloomshade Grove unlocks official citadel access if you would rather fight that boss instead of using the gap. You do not need a separate quest item after you are standing in Martyr’s Prison.

Widow’s Overlook to Blackridge Hamlet

This is the early overworld run if Gloomshade Grove is not lit yet. Stay on the beacons and do not drift into the citadel once the village is behind you.

Rest at the Widow’s Overlook beacon and open the map. Run north to the Blackridge Pass beacon. That is the first safe rest on this route.

From Blackridge Pass, take the path into Blackridge Hamlet. Use Mother’s Breath on the corruption wall that seals the village. The wall opens only after that cleanse.

Push through the hamlet on the muddy main path. Clear the enemies that stand in the road and keep moving toward the well in the village. Do not drop into the well until you can see it cleanly.

Armored character running up a muddy path toward a wooden barricade — The run through Blackridge Hamlet toward a wooden barricade on the muddy path. Image: Cold Symmetry

Holding Cells to the swamp side

The well in Blackridge Hamlet drops you into the Holding Cells. That dungeon is a connector, not the weapon room. You are here to reach the far exit that puts you on the Gloomshade Grove / swamp side of the citadel.

Jump down the well. The Holding Cells title comes up as you descend the stairs into the prison corridors. You are in the right dungeon when that name appears.

Holding Cells title card as the character walks down prison stairs — The Holding Cells title as you descend the stairs into the dungeon. Image: Cold Symmetry

Stay in the dark corridors and skip the elevator in this dungeon. The elevator is the wrong vertical line. Keep walking the halls toward the later exit.

Fight the enemies in the corridors as they appear. A sidearm shot is enough to create space in the tighter halls. Do not stop to clear every side room unless a door is blocking the way forward.

Player aiming a sidearm at an enemy in a dark stone corridor — A Holding Cells corridor with the Fire (Sidearm) prompt up during a fight. Image: Cold Symmetry

Press the hidden wall button that opens the iron gate. Walk through and take the second exit, not the way you came in. That exit moves you out to the swamp side near Gloomshade Grove.

If you climb a rope back to the surface beside the well, do not drop down again. Turn away from the well, then look for the stone building and the prison door. Light Gloomshade Grove if you pass it, then continue toward Martyr’s Prison.

Take the Great Martyr’s Blade in Martyr’s Prison

The blade is not on the overworld. You have to finish the inner prison room. The dungeon entrance is on the citadel’s outer wall, often behind wooden boxes with miners nearby.

Enter Martyr’s Prison and take the elevator down. Walk the stairs and interact with the unmarked object on the shelf if you see it. That interaction drops you into the cell block.

Break the lock on your cell door if you spawn locked in. Follow the small tunnel, then clear the first enemies in the halls. Come back to the main block once the path is open.

Find the locked cell that holds a plate or button on the wall. Press that plate. The gate into the main prison room lifts, and a notification reads that a gate has lifted.

Notification box reading A gate has lifted with an OK prompt — The A gate has lifted notification after you press the prison wall plate. Image: Cold Symmetry

Clear the packed room behind that gate. A heavy enemy and supporting knights wait inside, and the door can close you in. You can bait them into the bars and fight through the gate, or use a Lute Sidearm to turn them on each other if you already have it.

After the last enemy falls, check the side of the room. A metal gate may open on its own, or debris and a last patch of corruption may still block a small alcove. Break the debris, cleanse any remaining corruption, and take the Great Martyr’s Blade from the stone altar.

You know it worked when the game shows New Weapon Acquired: Great Martyr’s Blade. The Big Boi trophy also unlocks at that pickup. Open the inventory and the greatsword is in the equipment grid, ready to equip.

Inventory grid with a greatsword selected in the equipment slot — The inventory screen with the Great Martyr’s Blade highlighted so you can equip it. Image: Cold Symmetry

If the altar is empty, you are in the wrong room or the side alcove is still sealed. Press the wall plate, finish the enemies in the circular hall, and open whatever still blocks the pedestal. The weapon only appears on that altar after the inner prison room is resolved.