Terceira

Terceira is a planet in the Cavalier system and a human Outer Colony of the United Earth Government. The planet is orbited by a single moon, Victory. A watery world, Terceira is home to volatile weather and vast oceans. Following the Human-Covenant War, Terceira was occupied by the United Rebel Front in 2552, leading to a protracted campaign until the United Nations Space Command was able to retake the planet.

Colonization
Terceira was colonized in 2440 and settled as an Outer Colony of the Unified Earth Government. A number of hydroelectric platforms and isolated research centers were established across the planet's oceans, providing meteorologists and scientists with vast volumes of research data on Terceira's extreme weather conditions.

Post-Covenant War
In late 2552, following the end of the Human-Covenant War, the United Rebel Front violently took control of Terceira, instigating revolts against the government. The United Nations Space Command began launching operations to recapture Terceira, but it would not be for several years until the Terceira campaign saw the recovery of the colony.

Inner-plated Mjolnir forearms gained popularity among Spartans while suppressing revolts on Terceira. In a highly classified operation, several CIO-armored Spartans were deployed to Terceira, where they captured and transmitted information crucial to the recovery of the colony from Insurrectionist forces. The United Rebel Front's scattered remnants regrouped on the hydroelectric platforms distributed across Terceira, leading to the UNSC to deploy a number of "wake siege specialists" to retake the platforms. These operators were armored in OCEANIC-class Mjolnir, specifically intended to be used in aphotic, deep-sea operations. After some years of conflict, the UNSC succeeded in recovering Terceira, but rooting out and eliminating the remaining insurgents and terrorists that hide across the planet has proven to be a futile effort.

In the latter years of the 2550s, Arthoc of the Brothers of Unending Ire launched a vicious ambush on UNSC forces on Terceira that claimed the lives of three entire squads of Orbital Drop Shock Troopers.

Geography
Terceira is a watery world with vast oceans and lush archipelago chains, often considered a blush, veritable paradise at first glance. However, the planet's beauty hides the native dangers of Terceira. With volatile and extreme weather conditions year-round, the long, winding stretches of islands on Terceira are affected by tsunamis and hurricanes, wreaking havoc on local populations. The swamps of Terceira are roamed by giant crocodiles.

Trivia

 * The colony is presumably named after an island located in the Atlantic Ocean; it is part of the Azores archipelago, a Portuguese autonomous region on Earth.
 * The War Games map Vertigo in Halo 4 is set on Terceira.

List of appearances

 * Halo 4
 * Halo: Legacy of Onyx
 * Halo Infinite