From Halopedia, the Halo wiki
Echo Five was a codename for an Orbital Drop Shock Trooper in Echo Team of the 340th ODST Combat Training Unit stationed in Special Warfare Center in Seongnam on Earth during 2552, to help test the MJOLNIR Mark VI armor.
In October 2552, Spartan-II Maria-062 was sent in training with Echo Team. During the armor test, SPARTAN-062 hurled a paintball grenade onto the middle of the unsuspecting ODSTs, neutralizing Echo 1 through 5. Echo Five and Echo Two required medical attention and a medevac team was dispatched for them. While the entirety of Echo Team was ultimately bested by SPARTAN-062, the ODSTs of Kilo Team managed to subdue the Spartan.
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