Threshold is a symmetrical Big Team Battle map set among Forerunner structures inside an icy volcanic crater. The overall shape of the map is a figure-8 revolving around a large central bridge with various smaller paths and infantry pockets scattered throughout.

Each base face the middle of the map, with the bridge running perpendicular between them. To the left of each base is a road that goes up a cliff then through a tunnel overlooking the central bridge. Beneath the tunnel and road is a small room with various entry points. To the right of each base is another road leading through and over a small rampart wedged between two cliffs. This rampart connects various tunnels and passages for infantry, and neighbors a large cave that houses a teleporter node connected to the underside of the central bridge. In front of this cave is an open junction connecting various routes and positions between the two halves of the map.

The goal of this design was to hearken back to BTB maps of old, particularly those of Halo 2. Maps like Relic, Waterworks, and Containment were big inspirations. I wanted to create a space where vehicles could really thrive, but also allow infantry plenty of opportunities to fight or avoid vehicles through clever movement and timed pushes.