So you mean something like...?

You are the generals of King Harald's great army, proudly leading your fellow soldiers and crushing his enemies as he seeks to expand his territory in neighbouring lands, but one day you hear news that Castle Onyxgate, the seat of King Harald's power, has been attacked and occupied.

You must now march, with your army, eight hundred miles home and liberate the crown jewel of your kingdom. The journey will be harsh and many dangers will try to impede you, from monster dens to assassins sent to stop you from reaching your goal. The more of your army you safely lead home, the better your chances of liberating it, but you know the true battle will begin at the castle gates. It will take everything you have to free the king yourself, or die trying.