Act 1 Quest 3: The Search for Cain - Diablo 2
Quest Location: Dark Wood, Stony Field & Tristram
Quest NPC: Akara in Rogue Encampment
Quest Goal: Rescue Cain from Tristram
Reward: Deckard Cain will identify items for free
To begin this quest you can either complete Act 1 Quest 2: Sister's Burial Grounds or inspect the Tree of Inifuss which is located in the Dark Wood. Upon inspecting the tree the Scroll of Inifuss will drop onto the ground for you to pick up; if you didn't have the quest prior to now you'll receive it.
If you are having trouble locating the Tree of Inifuss keep an eye on your map while you're exploring. The Tree of Inifuss gets its own unique marker on your map that will appear when you get close enough to it. A picture of this marking is shown below.
Tree of Inifuss Map Location.
Show the scroll you get after clicking on the tree to Akara in the Rogue Encampment and have her translate it to update your quest. Once this is done you'll want to head over to the Cairn Stones in Stony Field which is where you'll use the translated Scroll of Inifuss to solve the puzzle and open the portal to Tristram.
The puzzle you have to solve is pretty straight forward, each stone needs to be activated in the appropriate order and the Scroll of Inifuss will tell you what order that is (pictured below). Once you've opened the portal to Tristram once you'll no longer need to open in the same game again.
Inside of Tristram all you need to do to complete this quest is to free Deckard Cain who is found in the town square inside of a cage. Click on the cage to free Deckard Cain and he'll open up a Town Portal for himself and dip, once you've done this all that's left is to speak with Cain in town to complete it.
However, there is more to do in Tristram than just free Cain. You may be interested to learn that Tristram is the best location for leveling and power leveling new characters until about level 15. For more information about Tristram Runs and leveling check out my Diablo 2 Leveling Guide: Tristram Runs. What makes this zone good is high mob density and Champ/Boss packs as well as Griswold, the Unique.
Along with this being one of the best places to level up for newbie characters in the game it's also the only place you'll be able to find Wirt's Leg which is required to enter the Secret Cow Level. That's all there is to know about the town of Tristram! Well, final easter egg is this was actually the main town in Diablo 1 and Griswold was also the Blacksmith of that town, Wirt was there too, it was good times--apparently up until it wasn't anymore and everyone died.
Cain's Gibbet in Tristram.
Wirt's Leg and a pile of gold.