Winterized Vehicles were introduced to Halo 3 with the addition of the Legendary Map Pack. The "Winterized" versions of the vehicles blend in with their frosty environment, and thus are much more difficult to spot in-game. The only vehicle that received more than a new paint-job was the Hornet, which saw its firepower scaled down considerably.
Winterized Vehicles are Avalanche-exclusive, with the exception of the Hornet, which reappears in the forge menus of Sandbox under the guise of "Transport Hornet".
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