There are two sides, each with enough space to build. They have 9:59 Seconds to build, there is a timer in map and a lever on the top of the clock and near the right builder's space. You basically use this to build challenge each other.
Rules: No going under then out of the space when building.
You can go above and then go out of the space.
And that is it. Hope you guys have a lot of fun build challenging each other.