The second stage of Haas 2C rocket is being prepared for ground testing. It will be tested in final flight configuration, having integrated the fuel tanks and Venator rocket engine. Unlike Executor engine, the Venator engine will be tested in horizontal position, this being possible due to the absence of the turbopumps. However, after the maximum 30 sec. duration testing, the second stage will be also tested in vertical position, on the Executor engine rocket stand currently under construction.

The second stage tests will begin in January. At this moment the fuel supply system is being completed and the functioning parameters measuring equipment.

More details about Venator engine here.