From Halopedia, the Halo wiki
The Bronto is a large disaster-response vehicle.
Brontos are the size of small houses. They roll forward with steel tracks capable of maneuvering through muddy jungle environments with ease. The Gao Republic's Ministry of the Environment maintains at least one Bronto for the purpose of responding to disasters. On December 14, 2553, a Bronto led a convoy carrying President Arlo Casille when it was ambushed by two United Nations Space Command teams working in concert. A cyathea tree fern was felled to cut the rest of the convoy off from the Bronto, which was permitted to escape as soon as it was evident a trap had ben sprung.
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