MORTAL SHELL II WIKI

Updated 2026-08-23

How to Upgrade Weapons in Mortal Shell II: All 5 Tarforge Parts

There are five Tarforge upgrade parts. Four go to Franz in Marrow Keep; the fifth is installed at the forge itself. Here is where to find each one and what it unlocks.

Upgrade station: Tarforge in Marrow Keep · Total unlock parts: five

1. Muradean Actuator — Unlocks weapon upgrades

Enter the Disciple's Path through the Village Outskirts Beacon during the opening route. Open the chest immediately after entering the Beacon trial, then give the Actuator to Franz.

If a beta save skipped the tutorial, check your inventory first; otherwise the chest remains recoverable later.

2. Obsidian Lathe — Unlocks Sidearm upgrades

Start at Widow's Overlook, travel southeast to Martyr's Tomb, and loot the chest in the dungeon's back room. Return the Lathe to Franz to add the Sidearm branch to the Tarforge.

3. Etching Needles — Unlocks Tarstone leveling

Continue through the Glutted Mire after the Sunken Village Beacon. Progress beyond The Wandering Shepherd miniboss and search the chest near Ruk before the area's main boss. Giving the Needles to Franz enables Tarstone upgrading and leveling.

4. Foundry Stone — Unlocks smelting (refund upgrades)

Search south of the Outskirts of Mammon Beacon, near the enemy group at the gate beside the castle wall. The Foundry Stone enables Smelt Equipment, which lets you spend Gloom to remove weapon or Sidearm upgrades and recover the invested materials.

Balance Patch 1 made smelting cheaper.

5. Endless Core — Raises the normal level cap

Late in The Unfound Path, enter the Hidden Nave Beacon. Walk through the fog twice, collect the torch that appears on the ground, and use it to escape the fog route; the chest beyond contains the Endless Core.

Install this part through the Tarforge itself rather than handing it to Franz.

How to use each unlocked branch

Interact with the Tarforge from the side opposite Franz. Choose the weapon, Sidearm or Tarstone branch depending on the parts you have delivered.

Frequently Asked Questions

Where is the Tarforge?
The Tarforge is in Marrow Keep. Give the first four unlock parts to Franz; interact with the forge from the opposite side to use unlocked branches.
What does the Foundry Stone do?
It unlocks Smelt Equipment: spend Gloom to remove weapon or Sidearm upgrades and recover the invested materials. Balance Patch 1 made smelting cheaper.
How do I raise the weapon level cap?
Install the Endless Core (found in the Hidden Nave Beacon, late in The Unfound Path) through the Tarforge itself — do not give it to Franz.