You won’t always have a simple one-on-one fight between two opposing detachments. As any detachment with units within 15 cm of the enemy becomes engaged in a firefight automatically, firefights between multiple detachments are common.
Where either side has more than one detachment that have units that are within 15 cm of a particular enemy detachment, resolve this as a single large firefight.
You may very well find that you have a number of one-on-one and multi-detachment firefight engagements all in a single Assault phase.
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