Trial Chambers is a PVP & PVE Map/Datapack that implements a unique gamemode based on the new Trial Chambers. You can play in Teams or in Co-Op. The Goal is to kill as many mobs or players in a given time.
To play you just need to place the lobby structure by running the command /place template trials:new_spawn ~ ~-1 ~. Once placed you can just enter the building, select between Teams and Co-op and press the Start Game button.