Dr. Rivera was a human scientist investigating the location where Fireteam Crimson found the articact.

Shortly after arriving there, she and the other scientists were under attack from Covenant forces. Dr. Pierce told the scientists to run. As such, Rivera and the other scientists hid behind a shield wall until Fireteam Crimson could kill the enemies.[1]


  1. Halo 4, Spartan Ops - Episode 2: Artifact - Chapter 2: For Science