Onimusha: Way of the Sword — How to Get Iron Fast for Sword Upgrades

Iron is the bottleneck on Musashi’s sword. Every attack power increase runs through it, and the game hands it out in small amounts — two at a time from a chest, a few from a cleared quest — so the difference between a sharp blade and a dull one is mostly how thoroughly you sweep each area of Kyoto before moving on.

Quick answer: Kill every Genma, mini-boss and boss you run into instead of running past them, open every chest, and re-walk areas you have already cleared — loose Iron lying in the world respawns, while chests only pay out once. Then spend it at a Spirit Mirror under “Enhance Equipment/Abilities.”

What Iron and Tempered Iron are used for

Iron is the sword material, full stop. Sword upgrades raise your general attack power along with Issen and Oni Armament power, and they consume Iron early on before shifting to Tempered Iron as the better-quality version shows up later. Your clothing runs on silk and leather instead, and your gauntlet runs on Genma-derived materials, so Iron never competes with those two.

The level system is why demand is so high. Each of the three equipment slots caps at level 5, but you do not jump a level in one purchase. The sword needs ten individual upgrades to climb a single level, the same as clothing, while the gauntlet only needs five. That is a lot of small Iron payments for one visible tier.

Every Iron source, and which ones repeat

The single most important distinction is chest versus loose pickup. A chest is a one-time payout — once you have opened it, that container is finished for the rest of the run. Materials sitting out in the open world are not, which makes cleared areas worth revisiting.

Source	Repeatable?	Notes
Chests	No	One payout each, often small amounts such as Iron x 2
Loose materials in the world	Yes	Respawn, so re-lap areas you have already finished
Regular Genma and mini-bosses	Yes, per encounter	Drop materials when defeated; skipping them costs you Iron
Bosses	No	Award materials on defeat
Quest rewards	No	Rewards can be previewed before you commit
Yorimasa’s Monument	Yes	Sells items you may need for upgrading

How to farm Iron fast

Check what a quest pays before you start it. Hover over any quest marker on the map and the game previews its rewards. For main quests, the materials on offer appear in the bottom-left corner the moment you open the map, so you can prioritise the ones handing out Iron.

Buy the Oni Vision special skills as soon as you can afford them. Oni Vision: Treasures, Oni Vision: Treasures 2 and Oni Vision: Search Range together make world pickups far easier to spot, which matters most for the loose materials that keep respawning.

Explore with the scan running. Hold L2 and tap R2 repeatedly as you move through an area so nothing valuable slips past you. Break the environmental clutter along the way — pots, crates and the rest — since it feeds both materials and souls.

Musashi pushing through a dark warehouse with the Pursue the Nue objective on screen — Sweeping a warehouse interior during “What Lurks in the Shadows” — clutter and side rooms are where loose materials hide. Image: Capcom

Fight everything. Regular Genma, patrols and especially mini-bosses all pay out, and it is tempting to sprint past them when you are chasing an objective marker. Don’t. Each skipped encounter is Iron you have to make up somewhere else.

Musashi aiming a ranged weapon at an enemy during the Pursue the Nue objective — Clearing enemies during “What Lurks in the Shadows” rather than running past them. Image: Capcom

Open every chest on the route, including the ones tucked down side paths and up on rooftops. Because chests never refill, a missed one is permanently missed Iron for that playthrough.

Musashi running across Kyoto rooftops with the Pursue the Nue objective active — Rooftop routes during “Pursue the Nue” hide chests and pickups the ground path never leads you to. Image: Capcom

When you are one or two Iron short, lap an area you have already cleared instead of waiting on the next quest payout. The loose materials will be back. If you still come up short, check what is stocked at Yorimasa’s Monument.

Spending Iron at the Spirit Mirror

Equipment upgrading is not available from the start. It unlocks as you progress, like most of the game’s systems, and then lives inside the Spirit Mirror — the same rest point you use for saving, fast travel and appearance changes.

Interact with any Spirit Mirror and open its menu. Once unlocked, “Enhance Equipment/Abilities” sits as the second option in the list.

Switch to the sword category. Clothing, sword and gauntlet are tracked separately with their own material costs, so upgrading one never blocks the others.

Confirm the upgrade. The screen shows the exact material cost and the stat change before you spend, so you can see what a batch of Iron actually buys you in attack power. Whenever the game offers an upgrade prompt, take it — there is no reason to bank materials.

Tip: Order does not matter across the three slots. If you have the materials, upgrade all three.

Why your Iron count is not going up

If a farming lap comes back empty, the reason is usually one of a small handful of things rather than bad luck.

You are re-clearing an area where the pickups were all chest-based. Those never refill; only loose world materials come back.
You are collecting silk, leather or Genma materials. Those feed clothing and the gauntlet, not the sword.
You are running past mini-bosses to reach the objective marker, which cuts out one of the more reliable drop sources.
You have not bought the Oni Vision skills yet, so pickups outside your immediate path are not being flagged.

The confirmation that everything worked is straightforward. Open “Enhance Equipment/Abilities,” pick the sword, and the upgrade counter moves — ten of those and the sword’s level number itself ticks up, all the way to a maximum of 5.