Updated for Town Hall 18 (October 2026).
The Mine is the small, cheap Builder Base trap: a 1×1 hidden charge that you set to ground or air, which goes off about a second after an enemy comes within 4 tiles and splashes everything of that type within 5 tiles. It does 80 damage at level 1 and 180 at level 10, and pushes troops back a little. You get two at Builder Hall 3 and up to six at Builder Hall 10.
How the Mine works
Think of it as the Builder Base version of the Home Village Bomb, with two upgrades. It reacts faster, about 1 second after triggering compared with the Bomb’s 2.5 to 3 seconds, and it can be switched to air mode. Tap it in your base to change modes. In air mode it floats on a chain. It only ever hits one troop type at a time.
- Trigger radius: 4 tiles.
- Damage radius: 5 tiles, wider than the trigger.
- Since Builder Base 2.0, it needs a minimum spring weight of 2 to go off, so one Drop Ship skeleton wandering past will not waste it.
- It re-arms itself after every battle. Placing a new Mine does not use a builder, but upgrades do.
A single Mine will not kill much. Its value is in groups of low-HP troops: support units, bats and skeletons, or a pack of Raged Barbarians that a Mine softens up for your defenses.
Mine levels
| Level | Builder Hall needed | Damage | Cost (Builder Gold) | Upgrade time |
|---|---|---|---|---|
| 1 | 3 | 80 | 5,000 | None |
| 2 | 3 | 90 | 10,000 | 30m |
| 3 | 3 | 100 | 15,000 | 1h |
| 4 | 4 | 110 | 25,000 | 2h |
| 5 | 5 | 120 | 50,000 | 6h |
| 6 | 6 | 130 | 80,000 | 12h |
| 7 | 7 | 140 | 120,000 | 1d |
| 8 | 8 | 150 | 250,000 | 1d 12h |
| 9 | 9 | 165 | 500,000 | 2d |
| 10 | 10 | 180 | 1,500,000 | 2d 12h |
Number of Mines: 2 at Builder Hall 3, 3 at BH4, 4 at BH5, 5 at BH6 and 6 at BH10.
Ground or air: how to set your Mines
Look at your defense log. If ground armies are beating you, set them to ground; if air armies are, set them to air; if both, split them. Some specific uses:
- Air Mines around Firecrackers help clear swarms of Beta Minions.
- One air Mine in the right spot can stop a cloud of bats from a Night Witch. If Night Witches are common at your trophy range, a good split is ground Mega Mines for the witches and air Mines for the bats.
- Ground Mines on the outer edge of the base catch Sneaky Archers sniping from outside. Two Mines together kill Sneaky Archers and Beta Minions of a similar level, and three kill Raged Barbarians, but that spends most of your Mines on one spot.
- A ground Mine near your walls can stop a Bomber before its first throw and leave it weak enough for a defense to finish in one shot.
- Ground Mines can wipe Drop Ship skeletons, as long as a heavier ground troop such as the Battle Machine sets them off.
- If your Builder Hall sits near a corner, air Mines there disrupt air troops coming in from that side, especially with the Roaster or Air Bombs close by.
Mines count toward the trap limit on each stage (12 per stage at Builder Hall 10). The Builder Base guide covers how stages split your traps.
How to deal with Mines when attacking
- Lead with high-HP troops. A Mine barely scratches a Baby Dragon or the Battle Machine.
- Stagger low-HP troops instead of dropping them in one clump, so one Mine cannot hit them all.
- Before a Bomber goes for a wall, send a Raged Barbarian along that wall to check for Mines.
Mine changes since Builder Base 2.0
- May 15, 2023: level 10 added with Builder Hall 10; minimum spring weight to trigger raised to 2.
- October 20, 2023: damage cut at most levels, with the biggest cuts at the top. Level 10 went from 206 to 180, and level 9 from 187 to 165.
- April 27, 2026: Hammer of Building can now be used on Builder Base traps.
Mine FAQ
Can a Builder Base Mine hit air and ground?
Only one at a time. You choose ground or air mode for each Mine.
How many Mines can you have in the Builder Base?
Up to 6, at Builder Hall 10.
Why didn’t my Mine trigger?
It was set to the other mode, or only a very light troop such as a single skeleton walked by. It needs a spring weight of at least 2.
Sources: Supercell release notes (Builder Base 2.0 full patch notes (Supercell, May 15, 2023)) and in-game data.
