Combat is a term for Star Trek CCG 2nd Edition, meaning a personnel battle.
Some cards have game text allowing you to begin combat between personnel. For you to do so, you must have any number of personnel present with any number of an opponent’s personnel. The combat involves all of your unstopped personnel there, and all personnel there commanded by that opponent. If more than one opponent has personnel present, you choose which opponent to involve. You cannot begin combat at a headquarters mission.
Often, a card will require a certain skill or characteristic to begin the combat. For example: Destroy this event to begin a combat involving your personnel. You must have at least one personnel involved in the combat.
Total the Strength of all your personnel involved in the combat. Your opponent does the same for his or her personnel. Compare totals. The player with the higher total is the winner. If the totals are tied, there is no winner.