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Gohbus was suffering from terraforming failure which caused it to slowly disintegrate. Refugees took shelter on Gohbus Moon, but when the planet fell apart, they moon would be thrown into space, killing them. Meanwhile, Colin Phash, the psychic son of former senator Corbin Phash, had taken shelter there along with the senator's former aide, Andrew Ballenger. They were hiding from the Ghost Program. A wrangler named Randall had been dispatched to Gohbus Moon to locate them.
Randall planned on using "lobotomized" zerglings to find the psychic child. Smith initially objected to the plan, fearing these zerglings could not be controlled, but Randall assured him they had explosive collars which could be remotely detonated. He also pointed out the refugees weren't going to be evacuated on time anyway, so "don't you go whining about collateral damage". Smith was ordered to feed Randall any actionable intelligence on the child's location, and "no playing cavalry until I get the kid".
The zerglings were released, panicking the populace. During Randall's search, a frightened refugee, believing Colin Phash's powers had lured the zerg to their location, sent the marines a video confirming the child's presence there. Smith contacted Randall with the information.