Consider a player's avatar in Quake II. At any given time, it will be managed by a single node in the system (e.g., the node that the client is connected to). The player's think function will process input commands from the player, modify its position in the game, and other objects the player interacts with. Hence, the node requires the current game map, which is immutable and can be shared by all nodes (to facilitate collision detection, for example). In addition, the node must send the current view of the game to the player. As a result, all other objects, including other player avatars, monsters, items, and missiles, in the immediate vacinity of the player need to be present on a node. Moreover, the player's avatar may modify nearby objects; e.g., he might shoot a wounded monster, reducing its health and killing it. If the primary copy of the monster object is located on another node, the modification is sent to this node which determines the commit order of all updates. For example, if the monster picks up a health item while it is shot by the player, the primary determines the order of events and decides if the monster survives (i.e. picks up the health before being shot) or dies. Other objects, such as items, may not actually require periodic think function execution or have interest in surrounding objects, but are triggered when ``picked up'' (i.e., modified) by player avatars.