Mines & Emeralds

Mines turn spare heroes into emerald shards. The catch: each mine locks 4 heroes for the whole run — no damage and no arena (they can still be used in Siege). This tool shows the yield and the real cost.

Unofficial fan companion

Time Travel calculator: plan emeralds per 192 h cycle, the Infinity Gem and the 666 checkpoints

Server

Your owned heroes follow this server. Mining plans, favorites and hidden heroes are shared by all servers.

Miners Your best miners

Spare heroes that are safe to send — they only buff their own damage, so locking them in a mine costs you nothing elsewhere. Tap one to drop it into your plan below, or tap × to stop suggesting it.

Plan Build your mining plan

Add one or more mines and fill 4 heroes each — e.g. spares in a quick 4h mine, others in a 60h run. Tap a mine to make it active, tap a hero to drop it in (or drag), tap a slot to remove. Tap ♥ on a hero to favorite it, and Save plan to have it ready next visit. Impact: Mine Minor Major Never.

Suggest from

All mines

Yields rise with duration, but shards/hour is roughly flat (~0.4–0.5/H) for everything except the Great Mines (Lv 4000+, 192h → 500 = 2.6/H). Longer mines aren't more efficient — they just mean fewer re-sends.

Mine	Unlock Lv	Time	Emeralds	Per hour

Who to send

Spare self-only heroes (Mine) whose upgrades only buff their own damage, or whose only perks are all heroes' damage +25% or less or ally buffs — they still fight in Siege while mining.
Old starter heroes you've outgrown, not in your arena / event line-up (mined heroes still work in Siege).
Minor (Minor) heroes with one small perk: souls under +10%, or one all-heroes damage boost between 26% and 49%.
Medium (Medium) heroes with two or more small perks, or gold found, souls +10% or more, all-heroes damage +50% or more, click damage, or crit chance / damage — usable when you need more miners.

Never send

Daily-Quest heroes (Never) — you level these for quests.
Heroes with Event bonuses (Never), and Influence / Science / weekly rating / Siege / Lair or huge souls boosts (Major) — the % stacks up every week.
Your top DPS / crit-damage carries and whole-team buffers.
Brath the Merciless (Dark Ritual) and key PvP heroes you field daily.

From ~Lv 1500 you run permanent miners (60h, over and over) — a wrong pick is locked ~60h (less with Time-Warp), so favor green/yellow heroes. You can't cancel a mine once sent; Time-Warp and daily-quest free warps reclaim heroes and refund bottles.

What emeralds provide

Cache / Vault / Chest of shards — hero shards to summon & rank up.
A global DPS bonus (like Souls) just for holding them.

Clan The Great Clan Mine

A PvP mine that resets nightly: two clans battle for control. Tap Send squad to challenge the current owner — while your clan holds it, each member is rewarded for the time held, up to 500 Emeralds over the 24-hour period for the winning clan.

Heroes with the Pacifism trait can't be sent to this PvP battle (or the King of the Realm's castle) — but they can still work the free mines above to farm Emeralds.

Clan Clan mine rules and emeralds per day

The Great Clan Mine

Open it from the top of the map screen. Your clan must be in the top 100 of the weekly event.
You fight clans about 10 ranks above or below you in that top 100.
Each round lasts 24 hours from the daily reset. Rewards: up to 500 emeralds per member per day, collected right after reset; you do not have to fight to collect.
A team is 8 heroes; each horseshoe sends 4 heroes.
You get 10 free horseshoes a day in the mailbox. At reset they top up to 10, not more; if you hold more than 10 you get none.
Heroes stay in the mine until they die. Revive a dead hero for 10 bottles, or hire it again after a Dark Ritual. The daily boss after a Dark Ritual is safe for mine heroes.
To pull a team out, use the disband button in the defence list.
A common team: 15% all-stat buffers, Sun Zi and Frozen Elga.

Emeralds you can expect per day

Source	Emeralds a day
Clan mine, clan holding the mine	up to 500 per member
Free mines at about level 4,000: 9 teams, 36 heroes, no time travel	about 182
Same, with the 5 video time travels and one round of quest time travels	600 or more

One player's numbers at that level; yours depend on your mines and heroes. Use the calculator below for your own plan.

Calc Mine yield & opportunity cost

Add every mine you run and how many of each (most players stack several ⭐ 500-emerald mines). We total the emeralds and the hero-hours you give up.

Time horizon (days)

⚠ Opportunity cost

Dungeon Crusher HQ is an unofficial companion — always verify numbers in-game. Need spare heroes? Browse the Hero Database →