This also helps with the time objective and the Show no Mercenary objective. Kill the guards instead of escaping them.Weathering the Storm: Escape the pursuing Merryweather enemies in less than 4 minutes.Show no Mercenary: Eliminate all pursuing Merryweather enemies.Avoid hitting rocks on the ocean floor.
The following are the Mission Objectives required to obtain the Gold Medal in the mission 'The Merryweather Heist (Offshore)':