An active world can always be set inactive. An inactive world can only be
set active with a "wait" ThingAction, and a player Thing (of ID 0), and a
map. On activation, rebuild all Things' FOVs, and the player's map memory.
An active world can always be set inactive. An inactive world can only be
set active with a "wait" ThingAction, and a player Thing (of ID 0), and a
map. On activation, rebuild all Things' FOVs, and the player's map memory.