The mine in SteamWorld Build looks like a tower defence game. It is not, and the reason is in the enemy list.
Three of the four underground hazards cannot be killed or removed. The Creep spreads and stays. Worms kill your bots outright and can only be pacified. Hives cannot be destroyed at all — there are two in the Marshy Ruins and four bigger ones in the Crackling Depths, and the game is explicit that walling one off does not help, because it will simply spawn enemies out of the nearest walls instead.
That leaves enemy blocks as the only hazard you can actually eliminate. Everything else is a layout decision: where you dig, where you place the Thumper, where you do not build.
Once you accept that, the mine stops being a fight and becomes the same coverage problem as the town above.
The three layers
| Layer | Dig analogue | New resource points | New threat |
|---|---|---|---|
| Dusty Caverns | Archaea | Scrap Vein, Ironium Vein | Collapses only |
| Marshy Ruins | Old World | Fertile Soil, Gas, Crude Oil | Enemy Blocks, Creep, Worms, 2 Hives |
| Crackling Depths | Vectron | Vectron Scrap, V. Scrap Vein | Everything above, 4 larger Hives, tougher enemies |
The single most useful structural rule: any resource found in one layer also appears in the layers below it. Descending does not unlock a new economy. It adds two specific new nodes per layer and makes everything more dangerous. That means a resource you are short of is usually not “deeper down” — it is a node you have not built on yet, on a layer you already cleared.
Three forms of the same resource, and only one is renewable
| Form | Behaviour | How you collect it |
|---|---|---|
| Block | Pays out once. Then it is gone | Miners |
| Vein / geyser / vent | Infinite. Regenerates continuously | An Extractor, or Prospectors standing on it |
| Farm | Needs fertile soil, regenerates slowly | Prospectors |
This is why mines “run dry” as a complaint. Blocks are one-time, and a player who has been feeding their town by breaking Scrap blocks will find the supply simply ends. The fix is an Extractor on a vein — and the Scrap Extractor only unlocks at Milestone 7.
The same applies to Ironium and to Vectron Scrap. Vectron Scrap is the worst offender: each block gives exactly one Vectron Scrap, and those blocks sit almost always adjacent to enemy blocks, so every one you take is a fight. Vectron Veins with extractors are the only real supply, and Vectron Parts gate most Scientist buildings and the best turrets in the game.
Blocks you have to plan around
- Brittle Dirt — collapses the moment it is exposed. Treat it as a structural trigger, not a resource.
- Sandstone — Miners need Pickaxes, from a Pickaxe Maker. Keep a stock; it appears on every floor.
- Granite — Miners need Drills, from a Carburizing Plant, Milestone 12. This is the wall that stops mid-game mine expansion, and it is a surface building, not a mine upgrade.
- Magma Blocks — explode when exposed, and are the only thing that breaks Bedrock.
- Bedrock — nigh-indestructible otherwise. It is a map boundary that occasionally becomes a route.
- Enemy Soil — collapses like sand and spawns enemies when it does. Do not dig it while a Guard is out of position.
The collapse loop, and the one habit that prevents it
A collapse happens when you dig too many blocks without letting your Miners reinforce the walls. Rocks fall, crush bots, and block tiles.
The recovery is specific, and doing it in the wrong order doubles the work:
- Place a Pillar first.
- Then send Miners to clear the rockslide.
Clear the rocks without a Pillar and another collapse is likely, which is why players report “it keeps collapsing in the same place.” Space Pillars roughly every 4 to 6 tiles through any unstable area, before it becomes a problem, not after.
Wide-open excavation is also a trigger, which is why the review complaint that “there is no point in building rooms, you can just dig out all the available tiles” is not quite right — digging everything out is exactly what causes collapses.
The hazard answers, in order of permanence
Worms — permanent, pacify only. The only lethal hazard. Most enemies disable your bots and need a Mechanic to revive them; Worms kill outright. Place a Thumper Turret with its active range over the den. Then never remove it and never let it be destroyed, because the Worm comes back.
Hives — permanent, redirect only. Two in the Marshy Ruins, four larger ones in the Crackling Depths. They periodically send a horde. They cannot be destroyed, and blocking their path just relocates the spawn to nearby walls. The play is to make sure the path from the Hive runs through your turrets rather than around them.
Creep — permanent, contain only. Non-lethal. It spreads, slows bots on affected tiles, and blocks construction on them. A Guard Quarter with a flamethrower item is the standard containment tool. If you cannot build somewhere and there is no visible reason, check for Creep.
Enemy Blocks — killable. Green and slimy. They hatch when a block is broken in a way that gives them a path. Clear them deliberately, one cluster at a time — releasing several at once is the standard way to lose a Guard squad.
And a warning that costs people runs: hordes also spawn when you start unearthing a Rocket Part. Set your defences before you start the dig, not after.
The four bot classes, briefly
- Miners — clear terrain, expand the mine, unearth parts.
- Prospectors — carry output from veins, farms and extractors up the mineshaft. The throughput bottleneck.
- Mechanics — build and repair machines, and revive bots disabled by collapses or enemies. Without a Mechanic on a floor, a disabled bot stays down.
- Guards — the only thing that fights.
Add Conveyor Belts between extractors and the shaft to cut Prospector inefficiency, and remember Teleporters come from a blueprint in a large chest and need a Mechanic on that level — they pair up, and they are the answer to deep-floor travel times.
Getting in
The Abandoned Mineshaft repair needs 8 Boards, 1,200 money, 18 Engineers and a road to the Train Station. The road is the one people miss: no road connection, no mine.
Related guides
- SteamWorld Build guide — the town-and-mine loop and coverage radii
- SteamWorld Build worms — the lethal hazard in detail
- SteamWorld Build granite — the Carburizing Plant wall
- SteamWorld Build rocket parts — what you are digging for
- SteamWorld Build tools — Pickaxes, Drills and the workforce behind them
- SteamWorld Build Mechanized — how the DLC rewrites this whole layer