Horizon
The Colony Struck by the Collectors
Horizon was a temperate human colony on the galactic frontier that suffered a devastating Collector raid in 2185 and later became the site of the secret Cerberus husk facility known as Sanctuary.
Horizon was a temperate human colony on the galactic frontier, a world that had struck the so-called sweet spot for carbon-based life. Its fertile soil and thriving ecology made it a desirable settlement, but in 2185 it was struck by a devastating Collector raid, and during the Reaper war it became the hidden site of the Cerberus facility known as Sanctuary.
A thriving frontier world#
Horizon was a temperate world that had hit the sweet spot for carbon-based life, with a nitrogen-oxygen atmosphere maintained by abundant indigenous photosynthetic plants and bacteria. While the native plants were not especially palatable to humans, the soil proved well suited to a handful of introduced Earth species, and a thriving human community grew up around its farms. Colonists took strict care to prevent ecological disasters, often planting genetically engineered crops that grew nutritious but sterile to limit the risk of outbreaks. The world's animal life was undergoing an explosion of diversity reminiscent of an early evolutionary age, and large flying insect analogs took advantage of the thick atmosphere and low gravity to grow enormous. Census data gathered by the Collectors placed the human population at around 643,000.
The Collector raid#
In 2185 Horizon became a target of the Collectors, who had been abducting whole human colonies across the frontier. Despite a Systems Alliance defense effort organized on the ground, the Collectors carried off roughly a third of the colony's population. The raid left lasting scars on the community and stood among the clearest evidence of the Collectors' campaign against humanity, a campaign that Commander Shepard was working to uncover and stop.
Sanctuary and the Reaper war#
When the Reaper invasion began in 2186, refugees streamed to Horizon, many of them landing illegally, until the colony's population could no longer be accurately tracked. They were drawn by galaxy-wide advertisements for Sanctuary, the world's main refugee center, which promised shelter from the war. In truth Sanctuary was a Cerberus operation. With all signal activity in the surrounding region jammed, the facility stayed hidden while it converted incoming refugees into husks as part of Cerberus research into indoctrination. The Reapers themselves moved against the world only once Cerberus had made headway in co-opting the Reapers' control over their creatures, by which time Shepard's intervention had exposed the Sanctuary sham to the wider galaxy. Most of the population that had remained after the Collector raid met their end there.
Frequently asked questions
- What is Horizon in Mass Effect?
- Horizon was a temperate human colony on the galactic frontier, a Systems Alliance world that had hit the sweet spot for carbon-based life. Its fertile soil and thriving ecology made it a desirable settlement.
- What happened to Horizon during the Collector raid?
- In 2185 the Collectors raided Horizon and abducted roughly a third of the colony's population, despite a Systems Alliance defense effort organized on the ground. The raid left lasting scars on the community and stood among the clearest evidence of the Collectors' campaign against humanity.
- What was Sanctuary on Horizon?
- Sanctuary was advertised galaxy-wide as Horizon's main refugee center, promising shelter from the Reaper war. In truth it was a Cerberus operation that converted incoming refugees into husks as part of research into indoctrination, kept hidden by jamming all signal activity in the surrounding region.
- What was Horizon's population and environment like?
- Census data gathered by the Collectors placed the human population at around 643,000. The world had a nitrogen-oxygen atmosphere maintained by abundant indigenous plants and bacteria, and its animal life was undergoing an explosion of diversity, with large flying insect analogs growing enormous in the thick atmosphere and low gravity.
- What became of Horizon after Shepard exposed Sanctuary?
- Once Shepard's intervention exposed the Sanctuary sham to the wider galaxy, the Reapers descended on the world. Most of the population that had remained after the Collector raid met their end at Sanctuary.
Sources
- WikiHorizon — Mass Effect Wiki entry
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