Test Subject 042

Test Subject 042 is an Easter Egg in form of a Test Subject featured on a clipboard found in the Enrichment Center. 042 appears to be a chicken that failed the tests it took. It is unknown if these tests involved the Aperture Science Handheld Portal Device, as they are never mentioned elsewhere.

Appearance
Portal: Still Alive Escape (Part 1)

Reference

 * https://half-life.fandom.com/wiki/Test_Subject_042