Cassandra "Cassy" Emily Arnold (Service Number: 37201-44556-CA) was a Sergeant Major (Previously was a Petty Officer First Class while in the Navy) in the Orbital Drop Shock Troopers and serve as the second-in-command of Delta-7 during the Battle of Earth. She was later conscripted into the Spartan-IV Program in 2556 due to her services in the corps and actions during the Human-Covenant War. Shee was then placed under the command of Logan Fhajad in Fireteam Sentinel. Later in mid 2557, Arnold and some members of Sentinel turned traitor and joined the Coalition of the New Earth Government.