1. A system comprising: a plurality of physical agents, the physical agents being configured for interaction with one another, each physical agent configured to: receive signals; perform actions in a physical environment in response to the received signals; and transmit signals indicative of the physical agent's state in the physical environment; at least one controller, configured to receive user input for controlling at least one of the physical agents, and further configured to transmit signals for controlling at least one of the physical agents; and a host device, configured to: receive signals indicative of the physical state of the physical agents; transmit signals specifying actions to be taken by the physical agents; store virtual representations of the physical agents, the virtual representations of the physical agents being configured for interaction with one another; and maintain substantial parity between the physical states of the physical agents and the states of the corresponding stored virtual representations by, for at least one of the physical agents: receiving a signal from the physical agent, the signal indicating a position of the physical agent; and responsive to the received signal indicating a position that differs from a position of a stored virtual representation of the physical agent, transmitting a signal to cause the physical agent to change its position to comport with position of the stored virtual representation of the physical agent.