Click on the picture of a kaiju to use it. Your money won't reset when you stop the game/restart. 1, 2, 3 and 4 is for attacking. I will be adding more kaijus! But you need to click on the picture of a kaiju, not the start flag, to start. But sometimes, the enemy don't get killed when you make it's HP below 1.
I made up most of them, exept the giant octopus. It is maybe from a kaiju movie or something!