Mining and power

Power is the only thing you buy directly. Everything else multiplies it. The result is measured in shards, and shards turn into CROWN through the daily pool.

Drills: base power

Drill power stacks: buying the iron drill on top of the bronze one gives you 5, not 4. The wooden drill stays in your chest forever and adds its 0.02.

Drill	Power	Presale	In-game price	CROWN per day	Payback
Wooden Drill	+0,02	—	free, everyone has it	0,13	—
Bronze Drill	+1	1 GRAM	200 CROWN	6,48	30,85 days
Iron Drill	+4	3 GRAM	600 CROWN	25,93	23,14 days
Steel Drill	+15	10 GRAM	2 000 CROWN	97,24	20,57 days
Mithril Drill	+50	30 GRAM	6 000 CROWN	324,14	18,51 days
Royal Drill	+130	70 GRAM	14 000 CROWN	842,75	16,61 days

Buildings: the speed multiplier

Every level of any building adds +20% mining speed, and levels of all four buildings stack. Upgrades are unlimited, the next level costs linearly more.

Building	Per level	Level cost, CROWN	Examples
Mine Shaft	+20%	200 × level	lv 1 200 · lv 2 400 · lv 3 600 · lv 5 1 000
Elevator	+20%	300 × level	lv 1 300 · lv 2 600 · lv 3 900 · lv 5 1 500
Warehouse	+20%	400 × level	lv 1 400 · lv 2 800 · lv 3 1 200 · lv 5 2 000
Smeltery	+20%	600 × level	lv 1 600 · lv 2 1 200 · lv 3 1 800 · lv 5 3 000

The first level of each building was also sold in the presale for GRAM: Mine Shaft — 5 GRAM, Elevator — 10 GRAM, Warehouse — 15 GRAM, Smeltery — 30 GRAM.

Boosts: buy once, keep forever

Boosts never expire and stack with each other: all three together give +60%.

Boost	Speed	Presale	In-game price
Small Pack	+10%	3 GRAM	600 CROWN
Medium Pack	+20%	10 GRAM	2 000 CROWN
Large Pack	+30%	30 GRAM	6 000 CROWN

Depth

The deeper the drill goes, the richer the rock: +5% per 5,000 metres, up to +100%. Depth is never reset.

Rock layers

The shaft is made of layers. In empty rock the drill moves faster but yields nothing; in ore and gold layers it is slower but pays.