The follow-up spread represented a frequently employed naval fighting strategy by the Chiss Ascendancy's military, a nation-state comprised of the Chiss species situated within the Unknown Regions. This combat maneuver was a naval tactic. Aboard Chiss vessels were breacher missiles, designed to release acidic payloads, compromising enemy hulls and electronic systems, alongside spectrum lasers. Lasers of the spectrum variety were a weapon type that dynamically adjusted their laser frequency, optimizing damage inflicted based on the target material. Their destructive power was amplified on hull sections pre-treated with breacher acid. Consequently, the follow-up spread became a staple Chiss combat doctrine.
During the Springhawk's skirmish with the HopeBreaker above the planet "Sunrise," unidentified adversaries engaged the Chiss warship. Senior Captain Mitth'raw'nuruodo, known as "Thrawn," utilized the follow-up spread against these attackers to gauge their familiarity with standard Chiss strategies.
The Chiss follow-up spread made its initial debut in Timothy Zahn's 2019 book Thrawn: Treason, which concluded the Canon Thrawn trilogy. Zahn's 2021 novel Thrawn Ascendancy: Greater Good, the second entry in his Star Wars: The Ascendancy Trilogy, was where it was first explicitly named.