Goblin Cleanup How to Clean With One Slime: Blood, Bundles, and the One Slime Army Achievement

Why One Slime Runs Are Harder Than They Look

Every swipe across a bloody floor pushes your slime closer to "blood sick" — the point where it stops cleaning and starts leaving messes of its own. That is why Goblin Cleanup how to clean with one slime is really a question about stamina management rather than mopping speed. If you want a practical answer to Goblin Cleanup how to clean with one slime, it comes down to three habits: swap slimes before they fail, keep every mana object in a safe state, and lean on fire slimes for range.

That matters because mopping is the core loop of this co-op Steam Early Access title, and because a single achievement, One Slime Army, asks players to clear an entire level's blood with exactly one slime.

What "One Slime" Actually Requires

The One Slime Army achievement is listed on TrueSteamAchievements with the description "Clean all blood of one level with only 1 Slime." As of 2026-11-09, that achievement page displayed a 1% unlock rate among the players the site tracks. It is a rare badge, and the wording is strict: one level, all blood, one slime.

The game is still moving, too. As of a 2026-11-09 capture of the Goblin Cleanup Steam Community hub, a pinned announcement reads "Goblin Cleanup | OUT NOW in Steam Early Access!" Mechanics described by players can therefore change between patches, so treat everything below as player experience rather than fixed rules.

The Three Slime Types at a Glance

The most detailed public walkthrough comes from a community Goblin Cleanup guide video, which describes three slime types. Two of them carry a one-slime run; the third is a niche tool.

All rows reflect player experience from community material, not official documentation.

Goblin Cleanup How to Clean With One Slime: The Bundle Method

The single most useful trick for Goblin Cleanup how to clean with one slime is to stop thinking of the slime as disposable. Slimes can be bundled together into a pile, and that pile becomes your supply line for the whole level.

• Build the bundle first. Find or create a bundle of slime before you start mopping, ideally near a safe spot you can respawn at. The guide warns that oversized slimes "kind of blow up," so do not over-feed the pile.
• Mop in short passes. Clean a patch, check the slime, clean again. Long sweeps burn a slime faster than most players expect.
• Swap the slime, not the run. Player experience reports that dropping a blood-sick slime back into a bundle and pulling out a fresh one gives you a clean slime again, while the dirty one simply stays in the pile. Expect Early Access patches to adjust this.
• Detach before you travel. Press X to drop the slime off your mop — the guide notes you cannot leave a level while a slime is still attached to you.
• Know your throw. Slimes can be picked up and thrown with right click, and the guide shows a thrown slime used to kill a skeleton in the crypt.

Read the Blood-Sick Warning Signs Early

A one-slime attempt fails quietly. The slime keeps working right up until it does not, so the players who finish these runs are the ones who notice the change first.

• Color shift. The base of the slime turns visibly red at the bottom, then drifts toward pink as it loads up with blood.
• The ghost icon. The clearest cue is a small ghost sprite with crossed-out eyes, which the guide shows appearing once the slime is fully blood sick.
• Mess on drop. A blood-sick slime dropped or dragged across a surface leaves new stains, which is the opposite of what you need on a single-slime run.
• Recovery options. Feed it to a mimic, or return it to a bundle for a fresh one. Hold E near a mimic to open its wheel, where you can also rename it and let it eat meat directly from your hands — faster than throwing meat on the floor, but it can swallow teammates too.

Fire Slime Is the Backbone of a One-Slime Run

Range is everything when you only have one slime. According to the community guide, a fire slime lasts far longer than a normal slime and cleans a noticeably wider distance, which is exactly what an achievement run needs.

To make one, overcharge a mana object to its highest setting and aim your slime on a stick at it with right click. You will see red particles and hear a sizzle, and the slime comes away burning. Two cautions follow immediately. First, an overcharged mana object damages anyone who touches it, so do not stand inside it. Second, put it back to normal power the moment you are done, or you leave a hazard behind and lose a usable mana object.

Not every flame works. Bonfires will light a slime; candles and candles on sticks will not, according to the guide. In Hot Springs the usable heat source has to be unlocked first, and the guide walks through using a golem to break open the lever that powers it. A blood-sick fire slime can be reset by sizzling it at a fire source again rather than being thrown away.

Treat fire slimes with real respect. Running into a wall while carrying one can kill you, and simply walking into one resting on the floor does the same.

Map Habits That Protect a Single Slime

• Keep mana objects in their middle state. Mana objects have three levels, and the extremes bite: the guide's mushroom example turns harmless at the smallest size, normal in the middle, and poison-spewing when boosted. Middle is safe, and it still counts as your mana object.
• Turn torches back on. Players routinely forget to reactivate lights after using them, which costs them mana and visibility later.
• Grab an ice slime at the right moment. The icy lake in Hot Springs only reacts when you throw a slime into it, and throwing it does not convert it back — the slime becomes an ice platform builder used to reach tickets.
• Respect the challenge levers. On the watchtower lights-off challenge, flipping the wrong lever instantly voids the run, so leave it alone until you are ready to leave.

FAQ

Can you really finish a level with one slime in Goblin Cleanup? Yes — the One Slime Army achievement exists for exactly that, described on TrueSteamAchievements as cleaning all blood of one level with only one slime. As of 2026-11-09, that page showed a 1% unlock rate among tracked players, so expect it to take practice with the bundle method and fire slime range.

How do I know when my slime is about to become blood sick? Watch the color. A red tint creeping up from the bottom and a pinkish hue mean it is loading up, and a ghost sprite with crossed-out eyes confirms it is blood sick and needs swapping or feeding to a mimic.

Is a fire slime worth the danger on a one-slime run? Community reports say it lasts much longer and cleans a wider distance, which makes it the strongest single upgrade to a one-slime attempt. The trade-off is real: it kills on contact, so never run into a wall while carrying one.

Where does Goblin Cleanup how to clean with one slime get easier with practice? Start on a map whose layout and item hiding spots you already know, practice the bundle swap until it is automatic, and confirm the light switches and mana object states before you commit to a full clearance attempt.