Buildings
The buildings
All seven buildings and both tap upgrades in one place: price, income per second, time to pay for themselves, and the numbers at ten copies.
Idle income in Crystal Cavern comes from seven buildings. This page lists what each one is, and how much it costs and earns, in numbers. How to decide what to buy is covered in Strategy.
All numbers are base values before cores. If you hold cores, income is higher by that much.
The seven buildings
| Building | First price | Per second (one) | Pays for itself in |
|---|---|---|---|
| Glowing MossMoss on the walls sheds crystal dust | 20 | 0.3 | about 1 min |
| Little DrillA clockwork bit grinds away at the wall | 180 | 1.8 | about 2 min |
| Bat PorterCarries crystals out of the dark | 2,200 | 11 | about 3 min |
| Ley PumpDraws up crystals with the groundwater | 26,000 | 62 | about 7 min |
| Crystal GolemDigs the seam open with a body of stone | 330,000 | 340 | about 16 min |
| Stardust ForgeTurns fallen star fragments into crystal | 5,100,000 | 1,900 | about 45 min |
| Core ReactorDraws straight from the heart of the planet | 82,000,000 | 11,000 | about 2 hours |
"Pays for itself in" is the price of the first copy divided by its income per second. The stronger buildings further down take longer to earn back their price.
Ten at a time
Each copy of a building costs 15% more than the last. In return, every ten copies double that building's output: ×2 at ten, ×4 at twenty, ×8 at thirty.
The table shows the total price of going from zero to ten, and to twenty, of each building, and the income per second at that point.
| Building | Total for 10 | Per second at 10 | Total for 20 | Per second at 20 |
|---|---|---|---|---|
| Glowing Moss | 407 | 6 | 2,050 | 24 |
| Little Drill | 3,655 | 36 | 18,441 | 144 |
| Bat Porter | 44,669 | 220 | 225,377 | 880 |
| Ley Pump | 527,897 | 1,240 | 2,663,534 | 4,960 |
| Crystal Golem | 6,700,228 | 6,800 | 33,806,384 | 27,200 |
| Stardust Forge | 103,548,964 | 38,000 | 522,462,273 | 152,000 |
| Core Reactor | 1,664,904,896 | 220,000 | 8,400,373,776 | 880,000 |
For every building, "total for ten" divided by "per second at ten" comes out at almost exactly the same time as the first copy’s payback. The price rise and the doubling are balanced to match. That is why the tenth copy of a building you hold nine of is such a good buy: one purchase doubles that building's entire output.
The two tap upgrades
Besides buildings, two upgrades raise what each tap earns.
| Upgrade | Effect | First price | Price rise |
|---|---|---|---|
| Sharpen the Pick | +1 crystal per tap | 30 | about 32% each |
| Resonance Gloves | Each tap also adds 3% of your income per second | 9,000 | 50% each |
Sharpen the Pick is available from the start and goes 30, 40, 53, 69 and so on. The Resonance Gloves appear once your all-time total passes 6,000. Gloves stack, 6% for two, 9% for three, so the more your buildings grow, the more each tap is worth.
When you rebirth
Rebirth resets all buildings and both tap upgrades to zero. In return you get cores, which multiply all income. See How rebirth works.