EDI turns dude and sacrifices herself to infect the reapers with a virus to lure them all to Earth, the united galactic fleet finds a way to drop the intergalactic deuce on our planet and destroy it taking all le Repurs with it. All is good le humans lost their most prized thing but have saved the galaxy, humans are now demigods.
Renegade Ending
EDI hax0rs le Repurs allowing Shepard to control them, she/he turns all Borg Queen on the galaxy enslaving everyone putting himself in charge
Hidden Ending
"It was the 22nd century, mankind's darkest hour...."