Piranha Games, developers behind MechWarrior Online, have announced a single-player follow up in the guise of MechWarrior 5: Mercenaries.
There are seven minutes of pre-alpha footage above if you just want a feel for the game - it's due out in 2018 after all so you have plenty of time to find out more. They have explained a little about the plot, however, in case you're interested in the sequel to 2000's MechWarrior 4: Vengeance.
Set to be chronologically the earliest of the six titles released so far, in the midst of the Third Succession War as it continues to fracture the Inner Sphere. The year is 3015, and you will get to choose your allegiance as you continue through the single-player campaign, taking missions from each of the Great Houses.
Take contracts from the factions of your choosing and engage in tactical, first-person, PvE ‘Mech combat through an immersive, career-based Mercenary campaign driven by player choice. Victory, prestige, and profit will not only require skill on the battlefield, but in the acquisition, maintenance, and enhancement of your BattleMechs.
As mentioned, it's not due out until 2018, but if you're a player of MechWarrior Online don't despair as development on that will continue due to a dedicated team working on MechWarrior 5.