Two currencies
Coins are the match currency. They place and upgrade Farms, the Money Printer, the Mining Cave, towers, and the door. Gems stay in the lobby for pet hatches and are not a substitute when a tower button asks for coins.
Income buildings
| Building | When it helps | Limit |
|---|---|---|
| Farm | First waves. Short payouts, and you can place several. | Needs repeated upgrades or it falls behind tower prices. |
| Money Printer | Indoors, beside the Farms. | One play report cited about 300 coins every 5 seconds after upgrades. That is an example, not every printer level. |
| Mining Cave | After you unlock it from Lorenzo's crates. Scales toward Diamond Cave payouts. | Not a wave-1 building. |
During the first five waves, put a large share of the floor into Farms and the printer. Players who reach the later Easy bosses often run about 6 to 10 income buildings. That count is a practical target, not a placement cap published by the game.
Cash before wave 1
- Like the experience and join the Duni&Minion group for a reported 100 starting cash.
- Team up with friends for bonus coins during the round. The multiplier amount is not listed.
- Redeem FREECOINS for 1,000 Coins and COINRAIN for a reported 5,000 Coins while those codes still redeem.
Lobby coins are a separate sink. Opening a tower in your inventory and upgrading it there raises the version you bring into later matches. Observed lobby prices include about 250 coins for an early Cannon step, about 6,000 for a Mining Cave step, and about 17,000 for a higher Farm step. Check the button in your own inventory before you spend.
Where not to spend
Do not empty your coins into a fifth Crossbow if the door is still level 1. The door locks the next upgrade tier. Do not spend Gems on door repairs. Gems hatch pets. Use the payback calculator only as arithmetic on numbers you type yourself.