Building B is one of the main three buildings in gm_construct. Various anomalies have been encountered in its gm_construct 13 beta iteration.
Building B is a tall five-story complex close to Building A resting on some elevated land overlooking the Garage. Its inside differs from vanilla gm_construct as each floor has one corner cut out, making every floor visible from the ground to the ceiling. A ladder connects each floor, as well as the roof. Adjacent to the ladder is a similar opening going up to the roof but without its own ladder. Each level is labeled with a large decal of its floor number.
Next to the lambda spray on the wall is a breakable section leads to a vent system that connects the Oracle, Dark Room, and the Garage and White Room. On the opposite is a small vent that is breakable, although its purpose or significance is unknown.
- Semper and Dark figures can occasionally be found on the first floor.
- Climbing the ladder all the way to the roof and going over to the ladderless hole leads to a unique Portals event that deposits you outside in the air.
- A baby doll globe can potentially spawn in Building B, behind the breakable wall going to the Oracle's vent.