MOUSE: P.I. For Hire Weapons
This page sticks to claims cross-checked against official MOUSE channels, Steam materials, and fresh launch-week guides. Where the pre-release trailers and the April 2026 launch build appear to diverge, we flag that clearly instead of guessing.
Confirmed Basics
Fumi Games developed MOUSE: P.I. For Hire, PlaySide Studios published it, and the digital launch on Steam and current-gen consoles landed on April 16, 2026. Official store copy also confirms Jack Pepper, over 20 levels, and unlockable traversal tools such as wall-running, grappling, and double-jumping.
Why This Page Exists
The 2025 “Experimental Weapons” marketing push highlighted CLEAN-D, COOL-D, and MIND-D gadgets. After launch, a Steam developer reply said some trailer-era weapons and equipment did not make the final release build, so old previews should not be treated as a perfect launch list.
Internal Links
Pair this page with the Beginner's Guide for movement basics, the Collectibles hub for schematic routes, and the News page for future balance patches.
Cross-Checked Arsenal
The cards below only summarize roles and mechanics that were corroborated by at least two fresh sources during launch week. We avoid hard numbers unless multiple sources agree on them.
Jack Pepper's pistol is consistently identified as the early reliable all-rounder. Launch guides also agree that its first alt-fire becomes a three-shot burst for cleaner mid-range follow-up.
The Boomstick is the close-range burst option. Checked launch guides describe strong pushback and short effective range, making it especially useful when larger melee enemies rush your position.
The James Gun fills the Tommy Gun role. Multiple launch-week sources call out its strong crowd pressure, and cross-checked upgrade notes say its alt-fire rapidly dumps bullets to interrupt enemy attacks.
The Devarnisher is repeatedly described as the corrosive or acid-style weapon in the launch build. Cross-checked guides agree that it applies sustained damage over time rather than instant burst, and it is also cited as useful against shields.
This weapon slows enemies first and can freeze them completely when the meter fills. The sources checked agree that its upgrades focus on freeze speed, making it more of a setup weapon than a raw damage pick.
Launch guides describe Kiss Kiss as the explosive wave-clear option. Its shots can spread blast damage and burn pressure across groups, making it a stronger pick when arenas fill with clustered enemies.
Jar-Head is the launch build's main stun-focused weapon according to the cross-checked guides. Those same sources warn that its stun value does not carry the same usefulness into boss fights.
The Loose Cannon fires explosive cannonballs and is one of the clearest utility weapons in the checked build. Independent launch guides say it can break weaker walls while still serving as a legitimate heavy-damage weapon.
D-Namite is consistently described as throwable TNT. Cross-checked launch sources agree that it deals heavy explosive damage, breaks certain walls, and can help remove shields, but it does not have standard upgrade tiers.
Checked launch guides describe Hellrazor as a room-clearing melee-style weapon. The same sources also agree that it does not use the normal B.A.N.G. upgrade path.
Upgrade Rules
Launch-week weapon guides agree on the broad structure: weapons unlock through mission progress, while Schematics are spent later on upgrades. The same guides consistently refer to B.A.N.G. stations as the place where those upgrades are applied.
The most stable cross-checked rule is that most main firearms support Tier 1 to Tier 3 upgrades, while D-Namite and Hellrazor are the recurring exceptions. That makes early schematic spending more important than it first appears, especially if you prefer one or two core weapons instead of spreading upgrades across the whole wheel.
If you are routing a first playthrough, this page pairs best with the collectibles section and future schematic-location pages. We intentionally avoid claiming a single “best weapon” here because balance impressions can shift quickly after launch patches.
Trailer vs Launch
In April 2025, official marketing spotlighted three “experimental weapons”: the CLEAN-D Automatic Turpentine Cleanser, COOL-D Cold Steam Applier, and MIND-D Self-Aware Attitude Changer. Those names still matter for search intent, but a post-launch developer reply on Steam says some weapons and equipment shown in older trailers did not make the final release build.
2025 Trailer
Officially marketed as the Automatic Turpentine Cleanser, with trailer copy describing corrosive cleaning fluid and stain-erasing damage.
2025 Trailer
Officially marketed as the Cold Steam Applier, built around freezing enemies in place before they shatter.
2025 Trailer
Officially marketed as the Self-Aware Attitude Changer, with hypnosis or mind-control style behavior in pre-release descriptions.
The cautious takeaway is simple: if you are looking for the exact launch arsenal on PC, PlayStation 5, Xbox Series, or Switch 2, prioritize launch-week guides and official post-release materials over 2025 preview trailers. If a future patch or DLC reintroduces trailer-era gear, we will update this page and link it from News & Patches.
Version Note
This page was written on April 23, 2026 using official store and FAQ material, launch-window Steam announcements, and fresh third-party guides published between April 16 and April 20, 2026. That makes it reliable for launch-window search intent, but not a permanent replacement for patch notes.
If you are reading this after a balance update, check the News page first. Anything involving damage tuning, ammo counts, or upgrade breakpoints is the most likely to change.