I was playing Halo Wars on the skirmish map Blood Gulch or Beasley's Plateau. I found a special feature called "Forerunner life support". I sent a squad of ODST marines in it, but I didn't see anything happen. So what does the Forerunner life support do?
I believe that's referred to as a Forerunner Lifepod in the Halo wikia. There isn't one on Blood Gulch IIRC, only a bonus reactor and supply depot on each side. They increase your population limit by 10.