Cards are special items used in magical research. Cards are required to upgrade jewels, forge, and other technologies. Unlike other boosts, the technologies invented with cards remain with you when you move from mine to mine.

 

You can find cards in chests: mined on the map, obtained from fixed shafts or cleared checkpoints, or bought in the store. Additionally, you get cards as rewards at the end of events if you’ve gathered enough keys.

What can you improve using cards? Well, everything! Cards are essentially needed to automate your shafts and increase their income. You can also increase the speed of their work to make gold faster. You can boost your forge to get more gold at the start of each mine. Can increase profit gained from rocks and mystery barrels. Reduce the goblin spawn time and their cost or increase the limit of goblins you can keep. Your goblins will work faster with the crit strike cards. And you can even increase the number of cards in chests!

Some of the cards are more precious and hard to obtain than others.  There are four types of rarity: Common, Uncommon, Rare, Legendary and Epic. 

 

 

Most of the mineshafts’ cards are common and uncommon, while most of the cards that improve your overall progress are rare and legendary (in the event maps, all cards have the same rarity).

 

Each jewel has two types of cards for improvement. Uncommon cards require more elixir for research and provide a bigger boost for the shaft’s income. Usually, common cards are enough to upgrade the jewel, appoint a manager and automate the shaft. But some mines have only a small amount of exact jewels, so an advanced level of technology is needed, and only your uncommon cards will be taken into account.

 

These cards will improve the work of your shafts and forge but are not required for automatization.

 

Crit-strike cards can improve the speed of mining. When the crit bonus is unlocked, your goblins will sometimes land a strong hit with amplified damage. The Crit Chance card increases the frequency of crit strikes. While the Crit Damage card multiplies the damage dealt by those strikes.