|The following is based on Fallout Shelter or Fallout Shelter Online and some details might contradict canon.|
“A ghastly Glowing One has taken up residence a little too close to the Vault, and it's drawing in Ghouls like moths to a flame. Extinguish the brilliant beacon before this Ghoulish gathering grows any larger!”
This quest requires the player's dwellers to kill the glowing feral ghoul, along with the other ghouls that have been drawn to it, that are roaming the area around the vault. Before it attracts even more of its kind.