Combat occurs when two characters (usually a PC and an NPC) are taking hostile actions against each other. Combat usually involves fighting and/or spellcasting, but can also involve other acts of subterfuge.
In general, combat is signified by actual combat with spells or boffer weapons. To attack someone, approach them and attempt to hit them with a weapon or a spell. If someone is approaching you, decide whether they are about to commit a hostile action and respond however you deem appropriate, such as defend yourself, counterattack, and/or retreat.
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