What, you thought the commander mode of Battlefield 4 was as big as it got? Enter Zeus, the upcoming DLC for ArmA 3. Set to release sometime in Q2, the free DLC aims to up the ante of the overlord player's role in modern military shooters. So what is it, exactly? From the site:

"Assume the role of game master and curate the experience of other ArmA 3 players. Wielding an intuitive real-time editor, you can manipulate or expand multiplayer scenarios on-the-fly, and create a surprising flow of challenges for the soldiers on the ground."

In summation, one player gets to be the Dungeons & Dragons equivalent of a Game Master in the classic cooperative, TDM and Sector Control modes, as well as a new game mode simply titled "Game Master". The game master has the power to spawn in units, vehicles, equipment, objectives and everything else you can imagine on the fly, which players will have to adapt to and improvise in order to succeed. The official announcement post for the DLC which is accompanied by the above embedded trailer, gives us some more details:

"Inspired by popular tabletop games such as 'Dungeons & Dragons', a limited number of players can assume the role of Game Master, and influence the multiplayer experience of those with boots on the ground. Watching the battlefield from a bird's-eye view, wielding an intuitive real-time editor, Zeus can create, manipulate or expand mission content to generate new stories and a flow of challenges."

That sounds pretty sweet, though you'll likely want to be playing with someone who isn't too abusive as GM. The Game Master role isn't nearly as restrictive as Battlefield's commander. Once again, the DLC is set for release sometime this spring or early summer, and is planned to cost absolutely nothing.