On the 5th of August the first expansion for the hit shooter Doom will launch across all three platforms (PC, PlayStation 4 and Xbox One). The expansion bears the name Unto the Evil, and it focuses on the multiplayer portion of the game. Even so, developer id Software has taken steps to insure they don't split the player community, and thus it will actually be possible to play the new maps without buying the expansion. All you need is a friend who has done so.
The way it works is by the game checking whether the player owns the DLC pack before any of the new maps are pushed into the rotation. If nobody in the party has the DLC pack then the new maps will never appear, but at as long as just one player has Unto the Evil bought and paid for, everyone is good to go.
This method makes it possible for friends to share the cost of a single DLC pack, but at the same time doing so means they will always have to play at the same time in the same party.