» Mon Feb 14, 2011 8:13 pm
You'll need to do the "wild card" quest line if you're going to go around murdering everyone, but, you can side with the legion and massacre pretty much every settlement except the Fort, Cottonwood Cove, and Nelson.
I am vilified by everyone except the legion and can still do faction quests as long as I'm in disguise when I accept them.
You can also sneak kill members of a faction without it effecting your reputation with them as long as you're hidden and wearing that faction's uniform (sneak kill legion while wearing legion clothing).