  Collaboration is an integral part of human dialogue. Typical task-oriented
dialogue games assign asymmetric roles to the participants, which limits their
ability to elicit naturalistic role-taking in collaboration and its
negotiation. We present a novel and simple online setup that favors balanced
collaboration: a two-player 2D object placement game in which the players must
negotiate the goal state themselves. We show empirically that human players
exhibit a variety of role distributions, and that balanced collaboration
improves task performance. We also present an LLM-based baseline agent which
demonstrates that automatic playing of our game is an interesting challenge for
artificial systems.
