Command & Conquer 3: Incursion

Incursion was the working title of Command & Conquer III while it was being developed by Westwood Studios. It featured full 3D enivornments and control, much like Generals. In addition, it'd include a more down-to-earth GDI instead of the mech-toting faction of Tiberian Sun. It was the second Westwood iteration of the C&C3 idea.

Plot
Our knowledge of the plot is sketchy, at best. C&C III would begin with an introductory sequence showing a GDI Commando floating in space among the debris of the Philadelphia (which was destroyed by Nod off screen), musing on what led to this point. He doesn't have a lot of time, though, as he starts to reenter Earth's atmosphere to die, along with his unique Screaming Eagle power armour. [http://www.petroglyphgames.com/forums/index.php?act=findpost&hl=&pid=43862 Ishmael Isgreen speaks].

Later, GDI and Nod would face off in Area 51, where Nod was looking for an unknown item, while GDI was attempting to retrieve the only remaining suit of Screaming Eagle power armour. In the course of the mission, Initiative soldiers would inadvertedly activate the Chronosphere sealed within the vaults of the base (and some other RA-era tech), sucking Yuri (an acolyte of Kane) into the vortex and throwing him back in time to the 1950s, explaining how Red Alert 2 happened (as another branch of the timeline).

Not that much is known about the plot afterwards, but it is known that it included the Scrin coming to Earth, lured by the Scrin rebels stealing the Tacitus. They believed that Tiberium would kill off humans, but didn't account for the effect it had on some humans, the [[Forgotten. They were able to harness Tiberium's energies themselves, able to direct them against the Scrin, nullifying their powers or even controlling ion storms. They were supposed to be a playable faction in an expansion pack for incursion.