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Fallout: New Vegas Walkthrough Wild Card: Side Bets
Fallout: New Vegas Wild Card: Side Bets
The factions you have to visit are: The Boomers, Brotherhood of Steel, Great Khans, Omertas and White Glove Society. Each of these factions will have a quest associated with them. If you decide to finish their quest, you can tell Yes Man that they will support you in your fight at the Hoover Dam, or you can just skip their quest and tell Yes Man to ignore them.
However, once you get inside the Brotherhood of Steel's bunker for the first time, they will ask you to take your clothes down to your underwear and force you to wear an explosive collar and ask you to get rid of the NCR Soldier that has been camping around the Hidden Valley (you will have to pass a Speech check of 35 and 50 in order to make convince him to move on). Once you're done, head back to Elder McNamara and tell him that the ranger is not going to be a problem anymore.
Once you've visited all the factions, head back to Lucky 38 and talk to Yes Man.
Talking to Yes Man will automatically complete the quest.