As the probes began to move away from the planet, it became clear that the effects of the damaged layers were fading quickly. If the readings were correct, then in less than one light year, they would be completely gone, and there would be no interference when the Hunters tried to move to nearby star systems.
But the strangest thing happened as they reached the edge of the solar system. One after another, the probes were destroyed by a burst of energy, ending their transmission abruptly and preventing anything from leaving.
The Hunters scrambled to adjust, and the call was made to have the second wave of probes raise shields to see if they could withstand the effect long enough to see what was going on.
The probes weren't armed or really defended, but the shields were designed to deal with space debris and should provide some sort of protection.