|The following is based on Fallout Shelter or Fallout Shelter Online and some details might contradict canon.|
After a Vault dweller reaches level 3, they can be armed with a weapon that deals 2+ damage, up to three dwellers can be sent on this quest. After travelling for 5 hours, or using Quantum, the dwellers will arrive at a random location. During exploration of the building, a glowing radroach must be killed.
Random loot, which includes 2 Nuka-Cola Quantums, a Scoped .44 and some common junk will be found throughout the building.
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