STRATA is an idle RPG. You dig by tapping, your crew keeps digging while you are away, and everything you haul up becomes gear, buildings and depth.

Around that sits a walkable map of the region of Marren, a Little-Alchemy-style crafting system, twelve dungeons with bosses, and a story that writes itself page by page as you go down.

1. Make your delver. Name, build, skin, hair and coat colour, height. Purely cosmetic — none of it touches your stats. The name cannot be changed later.
2. Tap the shaft. Every tap digs. Depth is the big number up top; below it is the stratum you are currently standing in.
3. Tap fast. Taps less than 1.5 seconds apart build momentum — up to ×1.9 on your digging. Pause for two seconds and it is gone.
4. Build a Flint Edge. The coach hands you three Flint: Craft tab, one Flint in each of three bench slots, Craft. Your first weapon.
5. Equip it. Delver tab → tap the weapon slot → Wear.
6. Hire your first digger. Dig tab, under Tools & Crew. From now on someone digs for you, even when you are not there.

That is the machine running. Everything after this is expansion.

Depth and hardness

Every dig produces work. How many metres that becomes is decided by the hardness of the current stratum — and hardness climbs with depth considerably faster than your yield does. That is exactly why you need tools, a crew, and eventually the Reseal.

A tap also carries about 0.8 seconds of crew work with it, so digging by hand is always clearly faster than watching.

Sediment

Sediment is the currency. It comes from every dig, from finds, from fights and from commissions. It pays for tools, traders, the smith, blessings and the watch.

The small rewards

Idle work

The Idle work readout is everything digging for you: hired diggers, Clay Huts in the camp, golem companions, gear carrying a work value. It starts at zero until you hire or build. The crew digs at a deliberately stately pace: the hand leads, the crew holds the line.

Tools & crew

Every purchase makes the next one dearer.

Events

Timed events run at random and show as a banner above the shaft: a rich vein (yields ×3), soft ground (double speed), rockfall (work halved), a strange hum from below (find chance ×5), water seeping in (yields down to 40 %).

Resources turn up constantly alongside the digging — Clay Lump, Flint, Granite, Bone Shard, Iron Chunk, Spring Water, Whisper Dust, Silver Nugget, down to Meteor Iron and Diamond. Some exist only in certain regions: Peat and Bog Iron in the Fen, Echo Quartz in the Ribs, Sea Glass in the Saltmark, Grave Wax in the Parish, Lava Stone in the Caldera, Everice in the Frostcut.

The more of a resource you already hold, the rarer it drops — the ground tends to give you what you are short of.

Finds are the museum pieces: Old Coinage, Bog Amber, Garnet, Milk Tooth Tin, Whisper Opal, Grave Jet, all the way to A Compass, Pointing Down. Every find pays sediment and goes into the museum.

The rarity tiers are colour-coded the same way everywhere: common · rare · mystic · epic · legendary.

Put two to four things on the bench, then Craft. Recipes are written down nowhere — you find them by trying. The bench is honest about how close you are:

Discovered recipes land in the Ledger below your inventory. Craftmaster Odd on the map gives you a hint towards a recipe you do not know yet, every time you visit.

Three starter chains

3× Flint                  →  Flint Edge      your first weapon
3× Iron Chunk             →  Iron Block
Iron Block + Flint Edge   →  Iron Pick

2× Clay Lump + Bone Shard →  Idol
Idol + 2× Silver Nugget   →  Warded Idol     ring with a healing strike

Bog Amber + Flint         →  Amber-Locked DNA
DNA + Old Machine Core    →  Something Alive
Something Alive + Iron Bl.→  Golem           digs and fights for you

Underneath all that sits a large alchemy layer: Flint and Flint make Ember, Clay and Water make Mud, Granite and Water make Sand, Sand and Ember make Glass — and onward through tools, bone, wood, salt, ice and fire.

Batches and wear

If a resource sits on the bench in multiples, it crafts in batches — the bench shows ×3, ×5 and produces that many results.

Hammer, axe, saw, chisel, needle, still, stove and boat last between 12 and 30 uses, then break. That is normal — build another. Some recipes do not consume the tool at all; the bench notes "not consumed" when that is the case.

Seven slots: weapon · helmet · shirt · charm · ring · boots · companion. The values on them are power (damage), def (damage reduction), crit, luck (find chance), speed (dig pace and dodging) and work (idle work).

Infusing at the bench

Put one piece of gear and two of the same raw resource on the bench:

• Raw improvement — Bone, Iron, Flint, Clay, Silver, Granite, Night, Star-forged. Up to three times per piece; the name stays as it is.
• Element enchant — Ember, Blood, Holy Water, Thunderstone, Spring Water, Bottled Gale, Fertile, Everice. Exactly once per piece, ever. The piece takes a new name, a visible aura and a power in combat.

The eight elements

The wheel: fire melts ice, ice stills water, water drowns fire and softens earth, earth grounds thunder, thunder splits air and strikes water, air wears down earth. Halo and blood are an old feud and cut each other deep.

The more pieces carrying the same element, the stronger the effect — and if every slot carries the same element, it counts double.

Two pieces into one

If you hold the same piece of gear twice, you can feed the duplicate to the original: +12 % to all its values the first time, less each time after, capped at +120 %. On companions this reads as Level; on everything else as +1, +2, +3.

The smith and the wizard

The Gallery Forge in the Ribs hones your edge: +1 power on every weapon you carry, permanently. The first honing costs 500 sediment, each further one double the last, twelve at most.

The Fen Wizard unpicks a piece for 800 sediment. Enchants and improvements fall away, the piece remains — and afterwards takes new words as if the first had never been said.

Fights arrive three ways: breaches (something comes up through the floor while you dig), dungeons (voluntary, on the map), and the bosses at the end of a dungeon's waves.

Your numbers

Attacks

Higher levels shorten every cooldown.

Auto-fight

On by default. The delver fights on its own, favours the strongest attack available, and reaches for the Ward Pulse below 50 % health. The Watchtower in camp gives auto-attacks +25 % damage per level. That is what keeps you alive while you are not looking.

Losing, and loot

"You retreat, bleeding but wiser." You lose nothing. Improve your gear, come back.

Every win gives XP and sediment. Foes drop their signature gear — bosses always, as long as you do not already own it. Dungeon bosses additionally carry unique loot found nowhere else.

Drag to pan, pinch or use the wheel to zoom. The map holds regions, locations and dungeons.

Unlocking regions

A region opens as soon as your deepest shaft reaches the mark — whichever shaft that is.

Every region has its own strata, its own resources and its own foes.

Moving camp

• Depth, tools, crew and buildings belong to each camp separately. A new camp starts at 0 m.
• The old camp keeps digging. The crew you leave behind works in the background and sends sediment and depth up — offline too.
• Gear, recipes, museum, level and Deeds are global and travel with you.

Several shafts running at once is the real idle engine of the game.

The locations

The daily round

Taking everything means, each day: ring the bell, ask the oracle, follow the wisps, pass the lych gate, hand in the writ, sign the watch or collect its pay. On top of that come the daily shift the first time you open the game each day (sediment scaled by your streak up to seven days, plus a Hardtack) and the Tally, a second daily payment that grows with the streak — with a Nightiron Shard on top after seven days.

Twelve of them, scattered across every region. Each is a wave of foes, the last of them often a boss. Before descending you see the number of foes, the tier, and your own power — compare the two.

Dungeons go deeper when you clear them. Every run opens the next floor: more foes, tier ×1.6. The first run gives the unique boss loot; deeper floors pay in rare matter — nightshard, stardust, and meteorite from floor IV — and in dungeon-only ingredients that drop nowhere else.

You build with what you haul up. Every level costs double the last.

The museum

Every find is kept here — and can still be used at the bench. Four sets give permanent bonuses once complete.

Chapters of the Delver's Journal write themselves as you reach certain points. Read them in order — the island is one sentence, spoken slowly.

The Frame

While digging you turn up tablet fragments at particular depths. In the Tablets tab they sit as a loose pile beneath an empty frame: tap one, then tap its place in the frame. The cut edges fit only one place. Set it wrong and the cell shudders, nothing more — guessing costs you nothing.

Four tablets, 21 fragments. Each completed tablet gives, permanently:

Plus an artifact each for the museum. And when all 21 are placed, something opens.

There are three frames in total. The second appears once the first is complete, and its fragments surface during ordinary digging. The third is sent up to you by your background shafts — which means you must have moved camp and left old shafts crewed.

At 6,000 metres you reach The Vess: the floor of everything. The floor breathes. From there the Dig tab shows the Reseal the Shaft button — pressed twice, as a safeguard.

• The game saves itself on your device, continuously.
• Offline progress: your crew keeps digging while the game is closed — in the active camp and in every background shaft. Up to 8 hours are credited, or 24 hours with the Charter. You are shown what came in when you return.
• The Ledger (free): open an account and your save follows your account code to any device and backs itself up. Sync now writes immediately; Restore from ledger pulls the stored copy and overwrites this device's save with it.
• Without an account: export your save as a code in the Delver tab and import it on the other device. Exporting resets the device you left — the code is the save.

The Charter

Every Charter comfort is currently free — you are here before the gates opened, and the game counts that in your favour. One tap on Claim free is all it takes.

The principle behind all of it: power is never sold, only comfort and finery.

Twenty Deeds, from the first cut at 15 m to Bone-Deep at 1,200 m. Each pays out immediately — sediment, XP or material. They double as your progress list: when you do not know what to do next, read the Deeds.

1. Momentum is very nearly a doubling. If you are watching anyway, tap in rhythm.
2. Never leave a shaft uncrewed. A camp without a crew does not keep digging.
3. Sell nothing you have not yet built with. Almost everything is an ingredient somewhere.
4. Commit to one element. Seven slots in the same element count double — the largest single jump in combat in the whole game.
5. The daily round is cheap. The bell and the lych gate together are +40 % find chance for 400 sediment and two taps.
6. Place fragments the moment you find them. Four tablets together are +25 % to finds, yields, idle work and power. Nothing else gives so much for so little.
7. Do not put off the first Reseal. +25 % to everything is forever; the depth comes back in a fraction of the time.

It is not a cavern under Marren.

So dig, whoever you are. Dig kindly, dig in rhythm, and do not stop.