Regular towers automatically shoot at enemies that are in range. They can be upgraded twice. You can tap on rocks, trees, or creeps to make all regular towers within range shoot at them.
This is the most basic type of tower. It does good damage and upgrades well.
This tower shoots enemies with glue. The more glue gets on an enemy, the slower it moves. Glue wears off over time. The lowest level glue tower barely slows an enemy, but if you line up two or three of them, you can slow enemies a lot. Upgraded glue towers shoot more glue at a time and can slow enemies down much better.
This tower throws heat seeking boomerangs that explode on contact and do splash damage to enemies nearby. Upgraded boomerangs do more damage and have bigger explosions that do splash damage in a bigger area.
This tower does massive damage over time. It starts out doing very little damage, but does more damage the longer it fires at a single enemy (a red power meter shows how much damage it is doing). Upgraded flashlights have long range and do insane amounts of damage when at full strength.
The super towers don't shoot at enemies, you have to activate them. Once activated, they remain active for a limited amount of time. After they are used, they will recharge over time. When they are ready, there will be green lights on them. Each super tower uses the accelerometer.
This super tower summons a U.F.O. Tilt to fly the U.F.O. around the map. Enemies take massive damage if they touch the U.F.O.'s beam.
This Super Tower slicks the path with oil. Tilt to make the Creeps slide fast downhill or move slow uphill.
This super tower summons a giant spider! Tilt to move the spider around the map. Any enemy it touches will be webbed and slowed a lot.
This super tower creates a powerful whirlwind that can pick up Creeps (even the big ones!). Tilt to move the whirlwind in any direction along the path.