You begin playing Clash of Clans with just Barbarians, soon add Archers, and then gain Giants. You cannot advance their level until you build a Laboratory (marked Research). You’ll need a lot of elixir to upgrade them.
Note that while troops are being upgraded in the Laboratory, they cannot be trained. You may have to go hours or even days between starting an upgrade and being able to deploy that kind of troop once again.
Barbarians will attack the nearest target. Period. You have no control over them beyond where you initially place them. Whatever target is closest is the one they will attack. Level 1 barbarians have 45 hit points, do 8 points of damage per second, and cost 25 elixir to train in the barracks.
Once you have a Level 1 Laboratory, you can upgrade your barbarians to Level 2, which gives them 54 hit points, 11 points of damage per second, and raises training costs to 40 elixir. It costs 50,000 elixir to upgrade barbarians, and that upgrade takes 6 hours.
When you have a Level 3 Laboratory, you can upgrade barbarians to Level 3, at a cost of 150,000 elixir and 24 hours. Hit points increase to 65, damage to 14 per second, and training fees to 60.
For more details on Barbarians, see the Clash of Clans wiki.
Archers attack their targets from a distance and are the only female troops you will run across early in the game. Like the barbarian, she will attack whatever target is first in range. Archers are less robust than barbarians, starting out with 20 hit points at Level 1 – less than half as much as the barbarian. Archers do 7 points of damage per second and cost 50 elixir to train at Level 1.
With a Level 1 Laboratory, you can upgrade archers to Level 2, which slightly increases hit points to 23 and damage to 9 per second, but at a relatively high training cost of 80 elixir. Cost of the upgrade is 100,000 elixir, and it takes 12 hours.
Once you have a Level 3 Laboratory, you can upgrade archers again. At Level 3, she has 28 hit points, does 12 points of damage per second, and costs 120 elixir to train. Upgrade cost is 250,000 elixir and takes 2 days.
You will probably find Archers some of the most useful troops to deploy, particularly at higher levels.
For more details on Archers, see the Clash of Clans wiki.
The third troop type you receive is Giants, and they are truly formidable. They specifically target defenses, including cannons, archer towers, and mortars. Giants begin with 300 hit points at Level 1 and are slow, doing only 11 points of damage per second. Training costs 250 elixir – ten times as much as a Level 2 barbarian! Giants are big, but their size makes them slow. Then again, they can sustain over six times as much damage as Barbarians.
You can’t upgrade giants until you have a Level 2 Laboratory, and that will cost you 100,000 elixir and take 24 hours. Your Level 2 Giant has 360 hit points, does 14 damage per second, and costs 750 elixir to train.
Giants can’t be upgraded to Level 3 until you have a Level 4 Laboratory. The upgrade costs 250,000 elixir and takes 2 days, at which point your giants have an impressive 430 hit points, do 19 points of damage per second, and cost a substantial 1,250 elixir to train.
Once you have Healers, you will find Giants much more useful, as they are more likely to survive an attack that would kill Archers, Giants, or Goblins.
For more details on Giants, see the Clash of Clans wiki.
In addition to attacking goblin villages while training and well into your first weeks of game play, you will be able to add Goblins to your army. Goblins are fast and greedy. They will ignore all other targets and head right to the nearest gold mine, elixir collector, storage, or other resource building to acquire all the wealth they can. They move faster than other ground troops and do double normal damage to their favorite targets.
You need a Level 2 Town Hall before you can add Goblins.
A Level 1 goblin has 25 hit points (a bit more than the Level 1 archer) and inflicts 11 points of damage per second against normal targets – and twice that when attacking resources. Training in the barracks cost 25 elixir.
You can upgrade your goblin to Level 2 with a Level 1 Laboratory. This costs 50,000 elixir and takes 12 hours, at which point each goblin has 30 hit points and does 14 points of damage – 28 against resources. Training cost increases to 40 elixir.
A Level 3 Laboratory lets you upgrade goblins to Level 3, which means 36 hit points, 19 standard points of damage, and 38 points when attacking resources. Upgrade cost is 250,000 elixir and takes 2 days.
For more on goblins, see the Clash of Clans wiki.
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