Here is the full list of all 19 Rocket Blasters achievements.
Destroy Fifty Asteroids
Destroy One Hundred Asteroids
Destroy Five Hundred Asteroids
Destroy Ten Enemy Drones
Destroy Fifty Enemy Drones
Destroy One Hundred Enemy Drones
Destroy a Pizza Armada Battleship
Destroy Three Pizza Armada Battleships
Destroy Five Pizza Armada Battleships
Destroy One Colossal Dreadnought
Destroy Three Colossal Dreadnoughts
Destroy 25 Enemy Drones with Triple Blasters
Destroy 25 Enemy Drones with Side Cannons
Destroy 25 Enemy Drones with Energy Shield
Destroy 25 Enemy Drones with Destructo Beam
Enter the Ice Caves of Yorg
Reach a High Score of 100
Reach a High Score of 500
Reach a High Score of 1000