Nightstalker
The original Vault Dweller
If you look deeply into Lonesome Road's plot, Ulysses called the sixth courier (so, our Courier) to confront him there (expecting the Divide to kill him). You will say he wanted ED-E to launch the missiles. But, if he really wanted to destroy the Mojave Wasteland, he would have done it. I say, he has a 10 in Intelligence, so its stupid to say it. Also, he has walked the Divide for almost 3 times. If he wanted ED-E, he would have found it in the Silo. He wanted to confront the Courier in his temple, in the Divide's end. I think the nuclear missiles were an excuse to fight the Courier at its best.
Opinions, boys?
Opinions, boys?