Different towers work for different enemies. However, there is a universally accepted best tower in terms of DPS, and that is the Archer tower. When mowing down large numbers of medium health enemies, an all-archer strategy is the way to go, and is highly effective early to mid game
Archers can twice a second with the fastest cooldown time of all of the towers.
Archers deal 24 dps for all units
Archers have a starting range of 22, which increases by one meter every round
Early to midgame tower
However, if you are facing a wave with a large quantity of flying monsters, a mage tower is the way to go. They have a higher range than the archer tower, which makes them capable of doing more damage earlier. But the real kicker of the mage tower is its x4 damage buff on flying enemies and piercing damage, which is incredibly useful in the mid and later stages of the game.
Range: 30, increases by one for every level
7 damage, but x4 damage to flying enemies.
Nonflying dps: 7
Flying dps: 28
When facing large numbers of close together flying enemies, a mage tower will decimate the enemies.
Mid to late game tower
Now for the frost tower. Oh, the poor frost tower. This is a great tower to have in the early game, when trying to get on your feet and establish a better defense around your crystal. However, the tower slowly reduces its effectiveness over time, as the issue no longer becomes the speed of the enemy, but the health.
Slow cooldown, only slowing enemies in a 10m radius every 2 seconds.
They aren’t that great later in the game, or I have not been creative enough to find a way to make them so.
Cannons. AOE damage. Thats pretty much it. And also, flying units wont be affected by cannon attacks, so if you’re in a wave with a lot of flying monsters, change that cannon to a mage.