Power and Heat
Two things can silence a tower that has a target in its sights: no power, or a barrel too hot to fire. Both are easy to plan for and painful to forget.
Power
Every game starts with power on, and only games with power are ranked. Every tower needs power to run. The base gives you 60 power for free; everything beyond that comes from Power Plants. The top bar shows the power you are using against the power you have.
- Each upgrade raises a tower's need by a fifth of its level-1 need: a level-6 tower needs twice what it did at level 1.
- A tower that is not shooting drops to 1 power (lights and radar). It draws its full need only while it has a target, so a quiet flank costs almost nothing.
- Support Stations, Airports and Helicopters work all the time, so they always draw their full need.
- Towers of the same type built side by side are connected: each needs 25% less.
- Efficiency cards after a wave make one tower type need less, and the Power Plant's research cards raise plant output, lower every tower's need and raise the base's power.
What each tower needs (level 1)
| Need | Towers |
|---|---|
| 0 | Miner, Power Plant |
| 3–4 | Repair Drones 3, Cannon Tower 4 |
| 6–8 | Cold Snap 6, Acid Tower 6, Water Pump 6, Sniper Tower 8, Cluster Mortar 8 |
| 10–14 | SawBlade Tower 10, Helicopter 10, Magnet Tower 12, Support Station 12, Missile Silo 14, Drone Hive 14 |
| 16–20 | Airport 16, Gravity Well 18, Lightning Tower 18, Portal Tower 20 |
| 22–28 | Tesla Tower 22, Laser Tower 24, Railgun Tower 28 |
So the base's 60 power runs fifteen new Cannons, but only two new Railgun Towers.
When power runs short
When your towers need more than you have, the towers farthest from the base go short first. A gun that cannot get enough shows LOW POWER: it tracks its target but cannot fire. A tower with none shows NO POWER and does nothing. Towers do not slow down on low power; they stop. Planes already in the air run on fuel and keep fighting until the wave ends, then stay down.
Every tower has a small lamp on the front of its base: green has power and is idle, orange is working on full power, red is not working (no power, low power or switched off). You can switch any tower off in its panel; a switched-off tower needs no power, so you choose which towers run.
- Tips
- Your front line is farthest from the base, so it is the first to go dark. Build power before you need it, not when the lamps turn red.
- Check the top bar before a boss wave: every gun firing at once is when the need peaks.
- Switch off a tower that guards an empty stretch to keep a big gun running.
Power Plants
The Power Plant costs 200 gold, needs no research and does not shoot. A new plant makes 40 power, and each upgrade adds 20 more, up to level 5 (120). There are no cables: its power goes into one supply for the whole map, so build it wherever there is room. It can go on any tile a tower can.
- Height counts: a plant makes 8% more for every level it stands up, on a hill or on platforms.
- Power Plants next to each other make more.
- Every plant takes a spot a gun could have had: put plants on the spots your guns cannot use well, out of range of the path.
Heat
Some guns heat up as they fire: the Cannon Tower, Tesla Tower, Lightning Tower, Railgun Tower and Laser Tower. The build bar marks them with a heat icon. Heat works in every game, with power or without.
- Every shot adds heat (a Cannon shell 30°C, a Tesla bolt 55°C, a Lightning strike 85°C, a Railgun slug 220°C), and the barrel cools back toward 20°C on its own.
- At 400°C a Cannon, Tesla, Lightning or Railgun Tower shows OVERHEATED, smokes and stops firing until it is back under 250°C.
- The Laser Tower works differently: when its heat bar fills it fires one burst at double damage, then rests for 2 seconds. Higher levels build heat more slowly.
- The faster a gun fires, the hotter it settles. A level-1 Cannon never overheats on its own, but upgrades and fire-rate cards make it fire faster: from about level 5, a Cannon that fires without a break will overheat unless something cools it.
The tower panel has a heat gauge that shows how hot the gun is and what is cooling it.
Cooling
Cold Snap: a hot gun in a Cold Snap's range sheds heat twice as fast at Cold Snap level 1, plus another half for every level after (6.5 times as fast at level 10). Only the strongest Cold Snap in range counts, and a Cold Snap with no power cools nothing.
Water: water on a tile beside a gun cools it too: 1.5 times as fast with one water tile, 2, 2.5 and 3 times with water on two, three or all four sides. A water tile beside a gun shows a cooling pump.
Both add up: a level-1 Cold Snap and one water tile give 2.5 times.
See it in the game: select a Cold Snap and the guns it cools glow icy blue (faintly when a stronger Cold Snap does the work), and its panel says how many it cools, for example “Cooling 4 towers · heat drops 3× faster”. While you place a hot gun, its ghost shows the cooling that spot would get.
Chains share water: connected towers of one type share their water, so water beside any one of them cools them all. A chain counts one more water tile for each tower beyond the first, up to 12 tiles (7 times as fast): seven connected Cannons with seven water tiles cool 4.5 times as fast.
- Tips
- A line of Cannons along a river is cheap to power (connected towers need 25% less) and cool to run.
- No water where you want it? The bulldozer's Dig makes a water tile for 250 gold (see Terrain is a weapon).
- Put a Cold Snap where it both slows the path and covers your hottest guns: it does two jobs for one tower.
- Keep Infernos in mind: Cold Snap cannot slow them, and their heat clears slows off the enemies around them (see Armour, shields and flyers).
Same-type neighbours, Support Stations, height and good tower pairings are in the FAQ: Towers working together.
The Clanker says
Low... battery...