User blog comment:Redoalien/Most Useful Alien/@comment-3549757-20120102052129/@comment-3279837-20120102065619

And Heatblast can't control his light, so he can easily be spotted with such brightness. Chromastone can hide and turn off the light when something approaches. He just needs enough to be able to see, and not get caught. He won't use much light. And number six is optional, because it doesn't actually have any decent answer, but good choice.