UNSC discover that Halo is in fact a method of containing a parasite known as the Flood , by destroying all sentient life to prevent the Flood from spreading beyond Halo .
The Covenant call this relic Halo , and believe it is a weapon and means of transcendence .
UNSC discover that weapon is in fact a weapon of containing a parasite known as the Flood , by destroying all sentient life to prevent the Flood from spreading beyond weapon .
The Covenant call this relic Halo , and believe it is a weapon and means of transcendence .