Onimusha: Way of the Sword: How to Solve the Mask Puzzle in the Underground Laboratory

Published: 07:00, 05 September 2026
Share this story:
AltChar
Onimusha: Way of the Sword: How to Solve the Mask Puzzle in the Underground Laboratory
The puzzle with the mask might be the only genuine puzzle of the game, and it is a real shame Capcom didn't include more of these in Onimusha: The Way of the Sword.
The puzzle with the mask might be the only genuine puzzle of the game, and it is a real shame Capcom didn't include more of these in Onimusha: The Way of the Sword.

Shizuka's hints won't get you far with this one. The real answer to the mask puzzle in the Underground Laboratory is on a wall you've probably already walked straight past.

Puzzles are a rare thing in Onimusha: Way of the Sword, Capcom's samurai action reboot, but the "What Lurks in the Shadows" quest in the Underground Laboratory throws one at you. A mask sits locked inside a cage, guarded by four hanging masks above it, and you'll need to interact with them in the correct order to open the cage. Shizuka will chime in with hints as you struggle, but they won't actually point you towards the solution. The trick isn't in the room with the cage at all; it's on the wall behind you.

Where to find the mask puzzle

The puzzle sits inside the Underground Laboratory, in the shrine-like room where you find the caged mask beneath a large mural. Four masks hang from the ceiling directly above the cage. Interacting with them in the wrong order won't damage anything, so there's no risk in experimenting, but you'll want the answer sorted before you start firing.

AltChar
The real clue isn't above the cage, it's on the wall facing it, where each mask reappears lit from behind.
The real clue isn't above the cage, it's on the wall facing it, where each mask reappears lit from behind.

How to solve the mask puzzle

Turn away from the cage and look at the opposite wall. You'll spot the same four masks depicted in a set of round windows there, each lit from behind. Step outside that room entirely and look down at the floor. The light source behind each depicted mask casts a shadow, and each shadow has a different number of holes in it, one, two, three, and four.

AltChar
Step outside to see the shadows properly. Each one carries a distinct number of holes that maps back to a hanging mask.
Step outside to see the shadows properly. Each one carries a distinct number of holes that maps back to a hanging mask.

Match those hole counts back to the hanging masks above the cage. Counting the hanging masks left to right, the mask in the third position casts a shadow with only one hole, so that's the one to shoot first. The fourth mask casts a two-hole shadow, so it's second. The first mask casts a three-hole shadow, third. The second mask casts a four-hole shadow, so it goes last. In short, shoot the masks in the order three, four, one, two. Get that sequence right and the cage unlocks.

Quick tip: Check the shadows before you touch anything above the cage. Once you've counted the holes on all four, the order is fixed and won't change, so there's no need to double back and recheck mid-puzzle.

  DON'T MISS!

Latest Game News