User blog comment:ArchKnightUlthering/Metro 2033 Alternative Ending/@comment-174.253.134.16-20120925180319/@comment-4488593-20120925202730

If Artyom was given a resistance to their abilities during his trip to the Gardens, then wouldn't Zhenya have a resistance as well? But later in the book Zhenya is revealed to be KIA.