I lead various of multiplier sessions.
They tend to last between 2 and 3 hrs.
1st hr was usually design and building time. Players had to build individually, or in a team. No uploaded predesigned vehicles was allowed. Also, there were limits on either resources, or number of blocks.
2nd hr was the battle testing, which was the best fun. Typically end up unexpectedly but with a tons of laugh by each of participants. Such fun and great times 😉