Builder Hall 7 Guide: Giant Cannon and Drop Ships

What changes at Builder Hall 7

The Giant Cannon locks onto targets within 9.5 tiles but its cannonball keeps travelling far beyond that, hitting every ground troop in its path and knocking them back. It fires slowly, so it is strongest against troops walking in a line, such as a tank followed by its support.

You also get a third Cannon, a third Hidden Tesla, a third Firecrackers, a sixth Army Camp, another Spring Trap and 140 Walls. Total defenses rise to 21, but the per-stage quota stays at 13, so you now have to decide which defenses sit in which stage.

The Builder Barracks reaches level 9 for the Drop Ship, a balloon that targets defenses and drops Skeletons on them; its Skeleton Bomb ability drops a big barrel that destroys Walls and releases more Skeletons. The Battle Machine can reach level 20, and from level 15 his charged Electric Hammer chains lightning to nearby buildings. Star Laboratory level 7 lets troops reach level 14, and the Healing Hut can reach level 3. The upgrade costs 1,800,000 Builder Gold and takes 4 days.

Upgrade priority

Battle Machine levels 11 to 20 are all available at BH7, and level 15 is a real power spike, so keep one builder on him whenever Builder Elixir allows.

BH7 upgrades run four to five days each, so the Clock Tower boost now saves real time. Line up its free boost with your longest upgrades, and keep the Star Laboratory busy at the same moment so the boost speeds up both.

1. Star Laboratory to level 7 and your main troops.
2. Battle Machine to level 15 for chain lightning, then toward 20.
3. Sixth Army Camp. One more camp is one more group of troops in every attack.
4. Giant Cannon.
5. Builder Barracks to level 9 for Drop Ships, if they fit your army.
6. Healing Hut to level 3 and the Crushers and Roaster.
7. Storages for the 2,800,000 Builder Gold BH8 costs, then the remaining defenses and Walls.

How to choose a base at BH7

Put the Giant Cannon behind other defenses so troops line up in front of it, ideally near the Builder Hall, where the knockback keeps pushing attackers away from it. Because it outranges Cannon Carts in Mortar Mode, it also protects areas that would otherwise be sniped from the edge.

Drop Ships fly over Walls and go for defenses, and their Skeletons pile up on whatever they reach. Put a Crusher near your Firecrackers and Air Bombs so the Skeletons attacking them get crushed, and keep a Roaster close to clean up groups.

With 21 defenses and a quota of 13 per stage, at least eight defenses end up in stage two. Use that to make stage two a real second test: Hidden Teslas and a Crusher around O.T.T.O's Outpost catch troops that arrive with low health.

Drop Ships ignore the Guard Post even though it counts as a defense, and they target defenses before anything else. That makes the order of defenses from the edge inward important: Air Bombs and Firecrackers behind a ground defense get reached last, while a Firecrackers on the outer ring is the first thing they destroy.

Common attack strategies at BH7

Drop Ships behind Boxer Giants are the new option. Boxer Giants take the defenses' attention while Drop Ships bomb defenses from above; use the Skeleton Bomb on a Wall section in front of key defenses or on a cluster of buildings.

Night Witches and Cannon Carts stay strong. A level 15 or higher Battle Machine with a fully charged Electric Hammer can break a cluster of defenses on his own, so time his deployment for a dense part of the base.

Spread your troops when you expect the Giant Cannon. Troops walking in single file give it its best shot; deploying from two points makes it hit fewer at a time.

Choose the Reinforcement Camp troop with stage two in mind. Defenses there are often weaker but fresh, and your surviving troops come in damaged, so a tank such as Boxer Giants or a group of Night Witches gives the stage-two push a new front line. The Healing Hut at level 3 heals survivors by 12% of their health between stages.

Farming and resources at BH7

The Builder Hall now holds 1,100,000 Builder Gold and Elixir, and the Elixir Cart up to 1,000,000. Battle Machine levels from 11 to 20 cost between 2.1 and 3 million Builder Elixir each, so Builder Elixir becomes the resource you watch most.

Push your trophies up when your army can handle it. Higher Builder Base leagues pay more Builder Gold per star and larger Star Bonuses, and the Clock Tower at level 7 gives 26 minute boosts.

Mistakes to avoid

• Leaving the Giant Cannon in a corner where troops never line up in front of it.
• Stopping the Battle Machine below level 15, where chain lightning starts.
• Sending every troop in one line from a single point against a Giant Cannon base.
• Putting all 13 strongest defenses in stage one and leaving stage two almost empty.
• Leaving O.T.T.O's Outpost at a low level. Each upgrade adds hit points, damage and Zappies to the last defense of stage two.
• Skipping the sixth Army Camp because it costs Builder Elixir that heroes also need.
• Ignoring Drop Ship Skeletons when placing traps. Mines and a Roaster near your air defenses kill them before they pile up.