Thought about making this for this season's ladder and had some questions:Barbs are plenty quick, you just need the knowledge contained in this picture:
The halls of pain is pretty self explanatory, there's only 3 maps, look where the WP is, and run the path correctly. It shouldn't take too long to learn.
The halls of vaught diagram there is a bit less easy to decipher, but the trick is even easier to learn. On the left side of the top right panel is a picture of a painting on the wall. On the right side, there are 4 green highlighted bits. Nihl will always be in the branch where that painting appears on the highlighted section. So instead of having to run all the way down to the end of each branch, you just have to run a quick circle around the middle when you come down the stairs. I'm not sure I just made sense, and I don't feel like going back to make sure.
As for the snakes? Stack some PDR and they're a joke. Fifty or so is more than enough. The charges from the skeletons is much more worrisome at that point, and that's even more dangerous for anything that isn't a barb.
WW on the other hand is less than ideal, I like conc, others use zerk. Disregard the part about howling monsters away... just leap attack onto nihl and start hitting conc. You'll take next to no damage with your 20-30k def. Howl/warcry are more useful to the zerkers who will take hits while swinging.
20 sword mastery
1 ww/passives/zerk/bc, maybe a few extra into nat res if needed
rest into bash
gbane um (alternative is shaft, sols instead of Ums, and sanctuary or upped umum mosers, your losses are dwarf for raven on CBF, a chunk of def, and 5% dr, but it is a cheaper build and starts running before 85)
amulet of life everlasting
oath in whatever sword because I like swords
dwarf star (MDR helps vs the succis he spawns with, fire absorb helps vs his CE, and if he's FE)
nature's peace (the RIP isn't a HUGE deal as a couple CEs isn't the end of the world and you're only killing nihl, but combined with the fact it has PDR I don't think it can be beat, a 2nd dwarf would be fine here too)
dungos (string works fine too)
With that barb I've done well over 1000 runs (I've lost count, I just know I can account for 1000 over a 3 day span) and I don't think I've dropped below 30% health once, and I've only dropped below 50% a small handful of times. Hell, dropping below 90% is surprising. 30 second runs.
Add a might reapers merc and trav is a complete joke too.
Edit: oh, you just said "key runner" not "dkey runner" in your thread title I guess... I got distracted by the fact your post only mentions nihl/snakes ^^
I wouldn't touch t/h keys with a barb. Way too slow without port, any sorc with a decent merc can do those though.
I'm not sure what the economy's like right now, but both my key runners have been at the starts of s3/4 respectively, so trading dkeys 1:3 or even more was easy, it might be a bit saturated with them at this point though. But even 1:1 I'd still just run Ds, so long as you can get the others reliably, he has great drops on his own, you can level off him easily, and he's the fastest run without a maphack.