Echo Team started off doing incredibly well prior to the Chimeran invasion of the United States on May 15, 1953, and completing operations such as Operation Iron Hand. But on December 21, 1952 Echo's team leader Lt. Hank Leavitt was killed by a Stalker in North Carolina, in which Nathan Hale succeeded him.
Echo Team later bared the brunt of the Chimeran invasion of 1953 when the Chimera attacked SRPA 3 in San Francisco. After escaping San Francisco, Echo were then tasked with destroying a damaged Chimeran battleship in the town of Orick. While boarding the vessel, Echo discovered that the Chimeran fleet intended to breach the Liberty Defense Perimeter through Twin Falls, Idaho. Following the destruction of the warship, Echo later traveled to Twin Fall and activated the town's two defense towers resulting in the destruction of three other Chimeran warships and defeating a Mother spinner, which almost killed Joseph Capelli. However, Echo was too late in preventing several Chimeran ships including Daedalus' flagship from breaching the the Defense Perimeter and subsequently activating a Chimeran Tower in Bryce Canyon.
Echo Team extracted Dr. Fyodor Malikov from Station Genesis and tried to stop Daedalus from activating the next tower in Chicago, but only to discovered that the tower was being remotely activated by Daedalus in Iceland. Echo traveled to Holar, Iceland in an attempt to assassinate the Chimeran creature. But the operation failed in which team members Benjamin Warner and Aaron Hawthorne were killed by Daedalus and with Hale being mortally wounded but saved in time by Joseph Capelli.
On June 26, the remnants of Echo Team along with Major Richard Blake and X-Ray Squad participated in Operation Black Eden; in which they managed to set a fission bomb onto Daedalus' flagship and destroyed the entire Chimeran fleet over the Gulf of Mexico. Nathan Hale and Joseph Capelli were the only participants to survive the entire operation. Tragically, however, Hale succumbed to the Chimeran virus and was executed by Capelli.
- Lieutenant Hank Leavitt (Echo-One) - Original leader of Echo Team. Killed in action in attempting to destroy a Stalker production factory in Raleigh, North Carolina on December 21, 1952.
- Lieutenant Nathan Hale (Echo-Six, then Echo-Two and later Echo-One) - Current leader of Echo Team. Killed by Joseph Capelli after having succumbed to Chimeran virus during Operation Black Eden.
- Sergeant Benjamin Warner (Echo-Two) - Second-in-Command of Echo Team. Killed by Daedalus on May 17, 1953.
- Specialist Aaron Hawthorne (Echo-Three) - Killed by Daedalus on May 17, 1953.
- Corporal Joseph Capelli (Echo-Five) - Originally part of Alpha Team and Kilo Team. Discharged following the events of Operation Black Eden. Also as the Sole Survivor of Echo Team and Operation Black Eden.
- Sergeant Gaines - Killed in action during Operation Iron Fist.
- Sergeant Marvin Kawecki (Echo-Five) - Retired in Resistance: A Hole in the Sky.
- Corporal Pardo - Took part in Operation Iron Fist.
- Corporal Vedka - Killed in action during a search and recovery operation in Chicago on December 3, 1951.
- Corporal Tim Yorba (Echo-Four) - Killed in action during an assault on the New York Chimeran Tower on July 4, 1953.
- Private Cooper - Killed in action during a search and recovery operation in Chicago on December 3, 1951.
- Private Russ Dana - Killed in action during an assault on the New York Chimeran Tower on July 4, 1953.
- Private Henning - Killed in action during a search and recovery operation in Chicago on December 3, 1951.
- Private Jim Jasper - Killed in action outside of Huron, South Dakota on November 15, 1951.
- Private Obo - Killed in action during a search and recovery operation in Chicago on December 3, 1951.
- Private Oshi - Killed in action during a search and recovery operation in Chicago on December 3, 1951.
- Private Perez
- Private Tanner