Helldivers 2 begins with a propaganda video that takes place on Super Earth that shows a man having his family brutally murdered by a Terminid during an invasion with the intent for having you join as a member of the Helldivers in order to become part of an elite peacekeeping force, see exotic new lifeforms, and spread managed democracy throughout the galaxy. As a Helldiver, you are another dispensable soldier that is sent to fight and complete missions in completely different planets. There are currently two main enemy factions that are the Terminids and the Automtons.
