Camp McCarran (Part 1)

First up, find Lieutenant Gorobets just outside a big tent to the north. Chat him up about the First Recon team, then specifically ask about Betsy and Sterling. You'll learn that Betsy had a rough run-in with a Fiend named Cook-Cook, and it's really messed with her head. This kicks off the 'I Don't Hurt Anymore' quest.

Head into the nearby tent and talk to the First Recon snipers. You'll meet Bitter Root, who used to be a Great Khan. If you've got the Speech skill (level 30 or higher), you can pass a check for some bonus XP and learn about his past, including the Bitter Springs massacre.

Next, find Corporal Sterling. He's a former ranger who's now a sniper after getting injured. He's got a unique rifle called the 'La Longue Carabine'. Now, this is tricky: you can't just pickpocket it normally. The best way is to plant a more valuable weapon on him, hoping he'll equip it, which then lets you steal the Carabine. It's tough, but doable. Or, you know, you could get it from him the hard way.

Talk to 10 of Spades, a newer recruit. He'll tell you about his and Betsy's encounter with Cook-Cook. After chatting with the other squad members, find Betsy. She's got some… interesting dialogue, but your goal is to convince her she needs help. You can try a Medicine check (level 40) or a Speech check (level 60).

If those checks don't work, don't worry. Talk to 10 of Spades again about how to convince Betsy, then chat with Bitter-Root about Usanagi. Corporal Sterling can also offer his diagnosis: chronically wounded pride. Once you've gathered their input, go back to Betsy and tell her the squad wants her to get help, using one of their stories to convince her.

Once Betsy agrees to get help, report back to Lieutenant Gorobets. He'll tell you to visit Doctor Usanagi at the New Vegas Medical Clinic. Head there and let her know Betsy's on her way. That'll wrap up this quest!

Return to Camp McCarran and find Major Dhatri in the terminal building to the south. He's got three Fiends he wants taken care of: Violet and her dogs, Driver Nephi, and Cook-Cook. Cook-Cook is a good first target. Just remember, if you want the full reward, don't damage his head.

Before you head out, talk to Little Buster at Camp McCarran. He'll tell you about Queenie, a Brahmin that Cook-Cook is surprisingly sentimental about. This could be useful.

Leave Camp McCarran and head south-west, past the El Ray Motel, and cross the bridge over the highway. Keep going west along the train tracks, then follow the rubble to the west. Head between two buildings, and you'll find the ruins where Cook-Cook is holed up.

If you go around to the western side of the ruins, you can find Queenie. Killing her will make Cook-Cook go berserk and attack his own Fiends. This can be helpful, but watch out because his allies might accidentally damage his head, costing you the full reward. Cook-Cook has several Fiends with him, so staying at a distance and sniping them with a good rifle like the Gobi is a solid strategy.

Once Cook-Cook is dead, take his head. You can also loot the ruins; there's a recipe for 'Cook-Cook’s Fiend Stew' on a metal shelf. Before heading back, go south to find the South Vegas Ruins West Entrance. Beyond that is the entrance to Vault 3, which you'll need later, but it's not important right now. It's a good fast-travel point for your next target, though.

Return to Camp McCarran to claim your bounty for Cook-Cook. Then, talk to Major Dhatri again and offer to hunt down Violet. She's located in a trailer park south-west of the South Vegas Ruins West Entrance.

Before you head out for Violet, go back and talk to Corporal Betsy. Tell her about Cook-Cook's demise. She'll be a bit grumpy, but she'll give you $100 NCR (x3) and $20 NCR (x4) for your trouble.

Fast-travel to the South Vegas Ruins West Entrance and head south-west around the ruins towards Vault 3. You might stumble upon the Poseidon Gas Station on the way. When you get close to the fenced-off trailer park, pull out a good rifle like Ratslayer and start taking out Violet's dogs, including her favorite, Violetta. Then, take down Violet herself.