Solve the equation on screen to earn minerals. Spend minerals on upgrades and on miners that dig while you are away, spend gems on the second upgrade track, and sink a new shaft when a run slows down to earn a permanent multiplier. That is the whole loop; everything below is detail.
The mine fills most of the screen. Above it is the current equation and your mineral count; below it is the keypad used to answer. A row of icons across the top opens the menu, the settings sheet, the rewards panel, the leaderboard and the daily and weekly bonuses. The upgrades panel opens from the button over the mine, and the crew column beside the shaft shows the miners you have hired.
Nothing on the screen is timed except the combo. You can leave the game alone for as long as you like; the crew keeps working and the equation waits for you.
Each equation is a short arithmetic question: addition, subtraction, multiplication or division. Type the answer with the keypad and confirm it. A correct answer pays minerals immediately and adds one to your combo. A wrong answer, or skipping the question, only resets the combo — you never lose currency, miners or upgrades for a mistake.
The settings sheet controls the equation mix. You can turn equation types on or off, choose how large the numbers get, and decide how big numbers are written (plain digits, thousands separators, or scientific notation for very large values). If you want a gentler session, turn off the types you dislike; if you want more pay per answer, turn the hard types back on.
Consecutive correct answers build a combo multiplier. The multiplier grows with the streak and multiplies the payout of every answer, so a long run of correct answers is worth far more than the same answers scattered between mistakes. The combo indicator shows the current multiplier and how close you are to the next tier.
Some upgrades and rewards exist purely to protect the combo: a gem upgrade can make a single mistake only drop the combo instead of resetting it, and a rewarded video can be exchanged for an instant combo save when a streak is on the line.
Press and hold the mine face to mine. Manual mining pays a smaller, steady amount per tick and keeps earning while you read the equation or decide what to buy. It is never the main income source, but it means no moment in the game is wasted, and it gives you something to do during a slow stretch.
The upgrades panel is the mineral economy. Click power raises the base payout of every correct answer, so it compounds with the combo multiplier. Miner tiers hire crew who dig automatically, and each tier is a larger, slower purchase than the last. Deeper equipment tiers unlock later and lift the ceiling on both sources. Purchase buttons show the price and whether you can currently afford it, and the panel lists what each purchase changes before you commit.
A common rhythm is to buy a level of click power whenever a correct answer starts to feel small, and to save for the next miner tier whenever your income is steady enough to reach it. Neither choice is wrong; the game is balanced so that both progress.
Gems come from achievements, the daily question, the weekly contract and optional rewarded videos. They buy a separate set of upgrades: cosmetic pickaxes and outfits, quality-of-life automation such as automatic bonus claiming, combo protection, and the gem-only lines that appear later in a run. Because gems and minerals buy different things, there is nearly always a useful purchase available in one track while you save in the other.
Every hired miner appears in the crew column beside the shaft, stacked in depth with the newest hire nearest the front. Each miner can wear any outfit or pickaxe you own, chosen in the shop's wearer selector, so a long-running crew can be dressed however you like. The custom skin slot lets you upload your own pixel art for the player character and their pickaxe if you would rather not use the built-in cosmetics.
The daily question is one bigger equation per day with a gem reward. The weekly contract is a running objective that pays a larger bonus when it completes. The goals panel tracks tiered milestones through the whole game — first answers, first miners, equipment tiers, prestiges — and each tier pays a bonus and unlocks new content such as extra miner types and cave themes. Achievements run alongside, granting small permanent bonuses.
Prestige is the long game. Once you reach the prestige tier you can sink a new shaft: the current run resets — minerals, upgrades and hired miners — and in exchange you keep a permanent multiplier that applies to every future run. Cosmetics, achievements, goals and gem upgrades survive, so each shaft starts faster than the last.
There is no wrong time to prestige. As a rule of thumb, sink a new shaft when a full upgrade round takes noticeably longer than the previous one; waiting longer gives a slightly bigger multiplier, but the next run is usually worth more than the wait.
Rewarded videos are entirely optional. When one is available, a button in the rewards panel or next to the relevant bonus offers an in-game reward in exchange for watching a full-screen video. The ad only plays after you tap that button, and closing it early simply means no reward. There are no banner ads, no interstitial ads and no ads that interrupt play.
Purchases are optional too, and cosmetic or convenience only. Nothing sold in the game changes how fast it plays, and every item a paying player can buy can also be earned by playing.
Your save is written to the device you play on and can be exported as a text save code from the Save section of the menu. Creating a free account is optional and adds cloud saves and the leaderboard. The settings sheet also holds the sound and haptics toggles, the UI text size, the equation controls and the debug readouts for local stats and the crash log.