Meltdown

You need to use the light gun to shoot and destroy the various particles before the control rods are destroyed. As the control rods take damage, the walls of the reactor will slowly cave inward, decreasing the amount of space available. From time to time power crystals may appear; if shot, these will provide bonuses such as extra points, control rod repair, temporarily freeze the particles, more powerful shots, and more.

The game ends when the control rods have been completely destroyed causing the reactor to meltdown.