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Universe and lore
Snowbound is set in a snowy Forerunner area with two large Covenant bases at either end of the map. The two bases are joined underground by a cave, revealing a deep network of Forerunner structures underground. The planet the map is set on is a former Forerunner world controlled by the Covenant, not far from human-occupied space. On the horizon, two celestial bodies can be seen. The Covenant base is surrounded by a perimeter of Covenant automated plasma turrets that fire upon anything in range.
Snowbound is a medium-sized, semi-symmetrical map with two bases. The bases, known as High Base and Low Base, are connected by an underground tunnel network. Much fighting takes place in or around the shield doors found inside the bases. Rocky outcroppings are located along the southern and western edges of the map (Rock Side); Covenant-built automated turrets prevent players from exiting the map via its otherwise-unblocked northern and eastern edges (Tundra Side). When players venture too close to the map's boundaries, an alarm sounds, warning them to return to the bases before the turrets open fire.
Boundless is a map variant released to improve the gameplay balance, specifically as a response to reports of widespread shotgun-camping near the Shield doors. It was due to be released on September 16, 2008, along with TU2, but was delayed until September 23, 2008. Like Sand Tarp and Epilogue, it is included as a default map variant in Halo: The Master Chief Collection. The following is a list of changes made;
In the Halo 3 Beta, the engine incorporated real time reflections into many aspects of the game. The outside of Snowbound's bases, as well as the Ghost, player armor, and a few weapon holders, utilized the graphical enhancement of real time reflection. However, this was removed from the final version of the game.
This map, along with a few others, were originally supposed to feature Shade turrets and deployable lookout towers. They were removed in the released version, though tags for these Forge items still exist within the map's base coding.