I met with a member of the Conservatory, who explained that their group had partnered with the Arbiters of War in an effort to examine what was described as small pocket dimensions. In order to continue their research, they've been tasked to bring in adventurers to compete in a contest known as the Proving Grounds - a challenge where groups of heroes will not only face challenges before them, but must do so while another group faces challenges of their own. Perhaps if I participate in one, I can see what it is all about.