Im fairly new to the game and me and a few friends were having some fun against the AI (smashing asteroids into their planets with 7 Halleys, Zerg rushes etc.) and we couldn't figure out how to fire a second shot out of the Annihilasor without having to destroy one catalyst and rebuild it. We couldn't find anything anywhere. I wanted to know if there is a way to fire another shot out of the Annihilasor without rebuilding it. Due to balancing reasons there probably isn't but I would like to know if there is. Much appreciated.
On the top right of the screen you will see the planet drop down. If you have a laser built (or halleys), you can expand the dropdown to see the list of units. On the planet with the laser (or halley) you will see a button to use the device.