Protect the Flag!
(Rule)Description: If Ancient Helveticus is killed, leave the model in place to show where the banner has fallen. Regardless of the mission being played, the Ultramarine player now also has to full the victory conditions for a 'Rescue' standard mission, treating the sadly departed Helveticus as the objective. If the Ultramarine player is not in possession of the banner at the end of the battle, they lose regardless of any other victory conditions. If they have the banner, they only win if they have fulfilled the victory conditions of the original mission as well.