Well, unfortunately The Ultimate Guide to The Pit has gone poof. Hopefully its author has a backup to repost. In the meantime...
"What is the Pit"
The Pit is a two level underground area in the Tamoe Highland in Act 1. In Hell difficulty it has an area level of 85. What this means is that now that max treasure class is 87, champs and mini-bosses in The Pit can drop any item in the game (other than Cow set and Annihilius) due to their increased drop levels. This is the reason for its popularity.
"Where is the Pit"
As stated above, The Pit is in the Tamoe Highland in Act 1. The fastest route to it is to start from the Outer Cloister waypoint. Head outside and follow the path till it forks then take your pick of directions. (Correct path varies depending on the map.) One direction leads to the Black Marsh and the other to The Pit. If you see The Black Marsh coming up, go back and take the other fork.
"can a non-twinked Avenger paladin (conviction use) handle it, maybe even on nightmare?"
If you play right, I'm sure you can survive. The main problems you will encounter as an Avenger are the skeleton packs you won't be able to leech off of and Dark Archers that have annoying, but effective, AI. Those two monster classes also like to spawn with various nasty properties like Fanatacism, Might, Conviction, and Mana Burn. Would suck for you to get caught hacking at skelles you can't leech off of that are whomping you with Fanaticism and spectral hit then have a boss archer with Conviction and Mana Burn run up and start pinging arrows off your shield and, more importantly, into your tender flesh. Another problem is killing speed since you kill monsters one at a time and the idea behind Pit running is to kill fast to maximize drops per hour. The option to do The Pit in Nightmare is there, but it's pointless since you don't get the high level drops and there are better places to level in Nightmare. Your goal regarding The Pit is to be able to run it quickly and safely in Hell difficulty and an Avenger isn't going to be able to do that very well, sorry. If you like Paladins, your best bet is to build up a Hammerdin. They kill amazingly fast and you already have a starter +1 skill shield for him. Wind Druids and Skelemancers are also great options for Pit running. The +1 armor will help any of these characters get off the ground faster too. If you hang out in these forums for awhile I'm sure the build guides and extensive Pit info that got lost will be reposted.
If you're on USEast non-ladder I can help you twink your character with some gear if you like and/or do some leveling. I have D2 on 3 computers so we could level a new char fairly fast with a constantly full 4 player game with only 2 chars out getting the experience. PM me if interested.
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