Halo 4 Forge mode in development at Certain Affinity

Halo 4’s mapmaking Forge tools are being created by Austin-based Crimson Alliance developer Certain Affinity, representatives from the studio announced at the Rooster Teeth Expo today.
The updated Forge mode was shown off on stage during the Halo 4 panel at the event, showing off an unfinished user interface, but a ton of new user-friendly functionality. Players can now lock placed objects on the map, ensuring that meticulously-set elements can’t be bumped out of place. Moving your cursor over objects highlights them green and displays their name, making it easier to manipulate singular objects in a much larger pile.
Players can easily duplicate items on the map, making it easier to build structures like bridges and roads. Objects can also be magnetized, making them connect to other objects in pre-set ways — making the aforementioned bridge-building process a breeze.
The Forge mode has an entirely new lighting system as well, allowing objects placed in the map to both cast shadows and have shadows cast onto them. Builders can also set "Player Trait Zones" which alter any player parameter (run speed, jump height, damage reduction, and so on) as they enter a field placed on the map. Certain Affinity also revealed a new object: The "Grav Volume," a field which augments or reverses entirely the orientation of gravity for anyone who steps into it.
Certain Affinity is well-versed in Halo development, having created several map pack expansions for the franchise. We’ve contacted 343 Industries to try and get some screens or footage of the new Forge tools