Updated for Town Hall 18 (October 2026).
The Mega Tesla is a Builder Base defense that fires a heavy bolt of chain lightning every 4 seconds at both ground and air troops, hitting 896 damage per shot at max level and arcing to a second target for 60% of that. It unlocks at Builder Hall 8, goes to level 9 at Builder Hall 9 and level 10 at Builder Hall 10, and you only get one.
How the Mega Tesla attacks
Every 4 seconds it picks a target within 7.5 tiles and zaps it. If another enemy stands within 3 tiles of that first target, the bolt jumps to it and deals 60% of the shot’s damage. That is the whole attack: two targets at most, one big hit every few seconds.
The pattern makes it brilliant against small numbers of strong units and weak against crowds. A Mega Tesla can take apart a Hog Glider, Cannon Cart or Baby Dragon in a few shots, but each 4-second cycle only removes one or two small troops, so a stream of cheap units can keep it busy. The chain can even hit an invisible Sneaky Archer if the bolt jumps from a visible target next to it.
Unlike the Builder Base Hidden Tesla, it doesn’t hide underground. Attackers can see it from the scouting screen.
Mega Tesla levels and stats
Costs are in Builder Gold. Times are base values before any Gold Pass builder discount.
| Level | Builder Hall needed | Damage per shot | Damage per second | Hitpoints | Cost (Builder Gold) | Upgrade time |
|---|---|---|---|---|---|---|
| 1 | 8 | 380 | 95 | 700 | 3,000,000 | 2d |
| 2 | 8 | 416 | 104 | 800 | 3,100,000 | 3d |
| 3 | 8 | 460 | 115 | 950 | 3,200,000 | 4d |
| 4 | 8 | 504 | 126 | 1,100 | 3,300,000 | 5d |
| 5 | 8 | 556 | 139 | 1,300 | 3,400,000 | 6d |
| 6 | 8 | 612 | 153 | 1,500 | 3,600,000 | 7d |
| 7 | 8 | 672 | 168 | 1,700 | 3,800,000 | 8d |
| 8 | 8 | 740 | 185 | 1,900 | 4,000,000 | 10d |
| 9 | 9 | 816 | 204 | 2,150 | 4,800,000 | 11d |
| 10 | 10 | 896 | 224 | 2,400 | 5,800,000 | 12d |
Range is 7.5 tiles at every level, and the chain reaches 3 tiles. Building and maxing it costs 38,000,000 Builder Gold and 68 days of builder time.
Where to place it
Because swarms are its weak spot, surround it with splash. A Crusher or Roaster nearby clears the cheap ground units that would otherwise soak its shots, and Mega Mines on the approach do the same job for free. Against air, pair it with Air Bombs so Night Witch bats and Beta Minion groups don’t pile onto it unchecked.
Put it where the attacker’s tanks will walk into range while their support is still behind them. Since it handles air and ground, it is one of the few defenses that earns its place in the middle of either stage. From Builder Hall 6 onward, each stage has a defense limit (14 at Builder Hall 9 and 10), so decide early whether your Mega Tesla protects the Builder Hall or O.T.T.O’s Outpost.
How to beat a Mega Tesla
- Overload it. Raged Barbarians come in numbers, and it can only take out two per shot.
- Use Night Witches. Their bats keep the Tesla firing at throwaway targets while the witches and your tank work on it.
- Bring a Drop Ship. It can absorb several bolts, and the Skeletons it drops add more distractions.
- Don’t feed it one valuable troop at a time. A lone Hog Glider or Cannon Cart walking in by itself is exactly what it is built to kill.
What changed with Builder Base 2.0
Builder Base 2.0 (May 15, 2023) rebalanced the Mega Tesla along with the rest of the Builder Base:
- The chain hit on the second target dropped from full damage to 60%.
- Damage went down at every level, and the upper levels gained hitpoints. Level 9 went from 943 per shot and 1,956 hitpoints to 816 and 2,150.
- Upgrade times got much longer. Level 9 used to take 5 days and now takes 11.
- Level 10 was added for Builder Hall 10.
Before the update, a level 9 Mega Tesla was also one of the requirements for upgrading O.T.T.O’s Hut. That questline is gone: O.T.T.O now lives in the Stage 2 Outpost, and the Home Village’s sixth builder comes from B.O.B Control instead.
Mega Tesla FAQ
Does the Mega Tesla hit air troops?
Yes. It targets both ground and air units.
What Builder Hall unlocks the Mega Tesla?
Builder Hall 8. Levels 1 to 8 are available there, level 9 at Builder Hall 9 and level 10 at Builder Hall 10.
How many targets does the Mega Tesla hit?
Two at most: the main target and one more within 3 tiles, which takes 60% damage.
Sources: Supercell, Builder Base 2.0 patch notes (May 15, 2023); in-game data.
