Obtain the SoulForge Hammer. Enter /underworld and go to Dage (walk right and down) then click on the SoulForge in the center of the room and accept its quest. Obtain the following:
Defeat Zardman Grunts at /forest (walk right to find 3).
Purchase from Loremaster Sara's shop at /greenguardeast.
Elemental Rock Hammer
Defeat the Rock Elemental at /bludrut (exit up ladder from /bludrut2).
Turn in the quest and make sure the SoulForge Hammer is in your inventory. Clicking on the SoulForge will now open a merge shop.
In this new merge shop, you can make the Shadow Katana Blade. For it, you need the following:
Platinum Paragon Medal x15
Purchase for 1m Gold each from Dage's merge shop.
Complete Dage's "Embracing Darkness" quest from /darkally by defeating enemies in the same map. Dark Wisps stack to 2.5k.
Folded Steel x1
Complete "Forge Your Steel, Steel Your Resolve" from /darkally by obtaining the following:
Flame-Forged Metal x13
Complete "Need Flame" from Chanky at /underworld by going left until you can go straight down then head right to the frozen bridge. To complete the quest, defeat the Frozen Pyromancer past the bridge.
Obsidian Rock x108
Choose your method:
- Legion Tokens: If you're a Legion member, you can trade 2 LTs for 1 Obsidian Rock in the SoulForge, meaning you need 216 LTs.
- Member: Complete "Undead Legion Member Special" (click on Dage > SoulForge > Quests) by defeating Firestorm Hatchlings at /firestorm (right>up>right x3>up from starting screen) and Skeleton Warriors at /battleunderb. Stack both of the drops to 100 so you don't need to go back and forth. Whichever item you stack 2nd won't look like it stacks past 6 but this is a visual error - opening quests from an NPC will update it.
- Non-Member: Complete "Obsidian Mining" by defeating FireStorm Hatchlings at /firestorm. To get to them from the starting screen, go right>up>right x3>up.
Defeat Amia the Cult Leader at /fotia - they are located at the end of the map.
Weapon Imprint x15
Defeat Raxgore at /doomvaultb. You'll need to complete the quests at both /doomvault and /doomvaultb to access him as /goto does not work. If you've done this already, you can get to Raxgore faster by talking to Valencia at /museum and selecting Artifact Quests > Armour of Awe > To the Crossroads. Then talk to Valencia again and select Armour of Awe > AQW Legend/Hero > More Details > Helm Boss.
While fighting him, be careful as he can lock your abilities and has an ability called Counter Attack - you'll need to target off by clicking the X to the top-right of their portrait or pressing ESC. Use the chance to get the Helm of Awe if you haven't already.
Shadow Katana Blueprint
Defeat Jaaku at /shadowfortress - they are at the end of the map. If you'd like to, also obtain 888 Perfect Orochi Scales from the 3rd and 2nd Head of Orochi as these are used later. Complete the storyline from /shogunwar > /shinringrove > /greenshell > /heiwavalley > /shadowfortress to access these enemies.
Now that you have the Shadow Katana Blade, complete "The Edge of an Era" from /darkally. This rewards the Yokai Sword Scroll, which is used for the final quest. Obtain the following:
Perfect Orochi Scales x888
Defeat any Head of Orochi at /shadowfortress.
Oni Skull Charm
Purchase from Mitsu Bishi's rep shop at /akiba - he's located in the first room. You need Rank 10 Yokai for this.
Darkened Essence x600
Defeat enemies at /shadowrealmpast.