The activity in different parts of their brains also became more synchronised. Their low-gamma waves, in particular, became twice as synchronised when they were in their near-death state than when they were anaesthetised or awake. These features have been linked to conscious perception in earlier studies.
Tug of war is a sport that directly puts two teams against each other in a test of strength: teams pull on opposite ends of a rope, with the goal being to bring the rope a certain distance in one direction against the force of the opposing team's pull.
Wars are usually a series of campaigns between two opposing sides involving a dispute over sovereignty, territory, resources, religion, or ideology. A war to liberate an occupied country is called a  war of liberation ; a war between internal factions within a state is a civil war.