From Halopedia, the Halo wiki
The planet's equator is covered by an immense forest of spiny, vine-like trees. Its native wildlife includes Eiyaa-Mahtuhaas a species of large, presumably carnivorous quadrupedal creatures; several specimens of these creatures were kept at the UNSC facility located on the planet.
The planet's atmospheric composition makes Erebus VII habitable for humans, though extremely hostile indigenous wildlife has prevented the world from becoming a viable candidate for full colonization. Additionally, the interference of the UNSC's Office of Naval Intelligence have also prevented the consideration; ONI has established numerous facilities on the planet, though their research goals have remained unannounced.
In 2557, ONI lost contact with its research teams and the planet's facilities were left abandoned. Several remote contact teams were sent to determine the cause of contact loss, but they only found empty laboratories and were unable to determine the location of its staff. Research on Erebus VII has since been suspended by the Office of Naval Intelligence, and there is no plans to commit new resources. A War Games simulation of the abandoned facility was later used by UNSC Infinity's SPARTAN-IV complement for training.
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