I recently tried killing the Legendary Deathclaw with a character of mine that's never died, and I wanted to keep it that way. I play Very Hard hardcoe mode, and I assumed that the Legendary Deathclaw could one-shot me, though I didn't want to find out. I was very careful with my preparations for the fight and went through the Northwest to kill some Cazadors to make Turbo, and then I thought hard about what companions I would bring with me. I decided on ED-E because KNOWLEDGE IS POWER! and I needed his enhanced sensors on my low-perception character, just so I'd know where all the deathclaws were. Second, I decided on Lily. I needed a companion that would charge ahead and tick off the Legendary Deathclaw so that'd he'd go after them instead of me. Lily I saw as being fast enough to get out in front of me quick, strong enough to take a decent amount of hits and her melee tendencies would mean she'd stay directly up in that thing's face. My only worry was that Lily was also very aggressive, so she might charge ahead and end up getting the attention of waaay too many deathclaws. I didn't want to set her on passive though because then I was at the risk of the Legendary Deathclaw coming for me first. As I made my way through the cave, I reached the Legendary Deathclaw's lair quicker then I expected: I was not fully prepared and I didn't for him when I turned the corner so I didn't get a chance to pick off some of the others. Sure enough, Lily charged directly for him, grabbing the attention of two other deathclaws nearby. I immediately took some Turbo and started shooting away, but this thing didn't go down quick. After a wasted round in the Legendary's chest and head, I started shooting at the normal ones to get them off Lily. The entire time, Lily and the Legendary Deathclaw and his gang were having an epic gladiator-style fight right before my eyes in slow motion, with her sword and their claws swinging through the air. I managed to pick off one of the deathclaws before I realized, wtf, if Lily dies then I'm screwed too, so I snapped out of it and healed Lily when she had 32 HP left. Then I quickly picked off the second deathclaw healing Lily again. Now it was just Lily and the Legendary Deathclaw doing their slow-mo gladiator fight with me shooting on the side. I tried shooting the thing all over and was surprised by how durable the thing was. Finally, I gave up on trying to cripple a leg or a claw or the head and just fired wildly at the head, and it fell. Don't think I ever crippled the head though.
The whole thing was a big worry of mine, cause I thought if anything in the wasteland would ruin my character's no-death streak, it's the Legendary, but I think I played it pretty damn well, given the situation. And looking back on it, I wish I'd filmed the fight. It was decently long and all in slow-mo with Lily swinging her sword dramatically; it was just asking for some stupid video with dramatic music to be made.
Other than that, this isn't really a victory of MINE, but I found this funny:
One day I decided I wanted to clean out the NCRCF, so I did. It was easy of course cause at this point I was a high level. Afterwards I went to Primm to buy some stuff before heading back north towards Vegas. Along the road I heard gunshots and I was curious who it was. I saw someone fighting some geckos and I assumed it was a prospector and that they had the kill easy. Upon further inspection though I realized no, it was Sargeant Mcgee and those things were hurting him. I helped him out, but when the fight was done he had a crippled leg and about 40% of his health. I watched him for a bit, curious where he was going, before going about my business.
Probably about three in-game days later I paid the Brotherhood a visit. Again, I heard gunfire to the northern edge of Hidden Valley and wondered what it was. There I saw Sargeant McGee shooting at some scorpions. I thought "wtf is this guy doing" and immediately shot down the scorpions. He continued walking on with his limp and now he had two bars of health left. Again, I got impatient watching him cause the limp made him slow as hell, so I continued on to the Brotherhood.
Probably a full week later, I was headed towards Camp Forlorn Hope. I ended up at some point with a couple Cazadors and started fighting them. I got them down to one very injured young cazador coming at me when I had to reload. Just before it got to me, it died. However, it's body didn't fly backwards as if my companion (Boone) had shot it; it flew to the side. I thought "wtf who shot it" and looked to the side. And who did I see? SARGEANT MOTHER@%$*ing MCGEE. I was just laughing my butt off, astonished that this flippin' NPC limped his butt AAAALL the way over to Camp Forlorn hope with 2 bars of health and a varmint rifle. Dude was SOOOO close, I realized where he was headed and thought there's no way I can let the dude die now that he's THIS close, so I escorted him the short way there just to make sure there was nothing else that could kill him. Dude actually freaking made it. He's sitting on my game file in Camp Forlorn Hope on the brink of death. I thought it was the funniest thing that'd I'd repeatedly seen this guy throughout the wasteland over the course of a week, wondering where the heck he was going, and then he finally made it. I doubt there's many game files with him alive if he always does this, but still, makes me wish all NPCs manually walked to their locations like that. Sure was interesting to watch his slow-but-steady progress.