Plague.

Perdido Beach is now run by a boy named Albert Hillsborough, whose introduction of capitalist systems to the town has placed him in a position of considerable power. Albert sends Sam and others on a mission to find a new water source, Lake Tramonto, on the far side of the FAYZ, as the town's supplies are running low. Meanwhile, an infectious plague leading those who catch it to almost certain death is spreading in Perdido Beach. On the way to the lake, Sam's group encounters an old friend named Hunter who was banished from the FAYZ with the power to radiate heat within anything who has become infested with parasites and dies. A coyote who leads them to creatures that are causing parasitic insect infections. The group attacks the creatures, but Dekka becomes infested with insects in the process. Sam later saved her by cutting her open and removing the parasites. Upon reaching the lake, the group is once again confronted by the creatures, which have grown to the size of SUVs and are being commanded by Drake. The group escapes back to Perdido Beach. Drake travels to Coates Academy with some of the insects, having been commanded by the Gaiaphage to capture Pete. Upon their arrival, Astrid throws Pete to the insects, who realizes the danger and vanishes both the insects and himself; her hope was that Pete's death would cause the energy barrier to dissipate. Pete is later revealed to be bodiless but alive.