Oh No, Asteroids!

Presentation
Oh No, Asteroids! is a tower defense game where you protect the Earth from incoming asteroids. They come in number and have various sizes and durability. But you have a full arsenal of options to dispose them: mines, barricades, blasters, cannon, missiles, particle beam and tractor beam. Each structure has a specific range, rate of fire, damage dealt and push that modifies the asteroid velocity.

Atmosphere
In this game, the Earth has no atmosphere so it shows an unhappy face. The music is pleasant, almost relaxing. Background, asteroids, Earth and defensive structures create a great looking mix of pictures and vector graphics. The animations and rotations of the turrets is smooth but sometimes the turret shrinks and becomes invisible. This incorrectly informs the player that the turret got destroyed.

Gameplay
You use the mouse to create mines or platforms. On each platform you can build a turret. Once built, the turret can be upgraded for greater efficiency. All structures and upgrades cost some resources that you acquire by destroying asteroids. Mines are great to create large blast that destroy about any asteroid but get "consumed" in the process. Turrets are the backbone of your deference line. On one hand, blasters turrets are very efficient to destroy asteroids thanks to a high rate of fire. On the other hand, particle beam turrets are very efficient to repel asteroids thanks to their great force push. Other turrets lay between these two extremes and it's up to you to take advantage of them. The tractor beam attracts asteroids and thus requires an innovative placement compared to traditional tower defense strategy.
On top of the usual tower defense mechanics described above, you can move your turrets like units in most RTS: select a group of turrets, move it, assign a number to a group, recall the group with the corresponding number key. This is really fun to use, especially with particle beams and tractor beams because you can divert asteroids from chasing on Earth or send them back to where they came from. Unfortunately, when you manage to collide two asteroids, they don't damage each other. And the game doesn't reward you for doing so: you only receives resources and points when you destroy asteroids. All turrets are very resistant to asteroids hits so you'll never use the barricades and deploy active turrets instead. Moreover, if you place a group of turrets adjacent to the Earth, they won't move when an asteroid hit them.

Overall
A solid set of interesting mechanics that are fun to use but need some improved balancing. The game only has one level so it tastes like a starter.