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