Num-ships-in-battle
From FreeSpace Wiki
num-ships-in-battle Returns the number of ships in battle or the number of ships in battle out of a list of teams, wings, and ships. Takes 1 or more arguments... (all): Teams, Wings, and Ships to query (optional)
Notes
This SEXP can be used for one ship to check if its present and alive in the mission; or destroyed, departed, or vanished.