I'm not what you would call an expert player. I normally have 63K DPS, 27K HP, 280-320 resistances, and 3K armor which should be enough to take out the big D based on several youtube videos I've seen where people with much less gear than me have killed him. But I just couldn't get the timing right on the 2nd stage. Either a shadow clone or Diablo always one shots me somewhere. I tried almost everything, including going almost all glass cannon with 75K DPS but only 11K HP and all I had to show for it was hundreds of thousands in repair bills.
Finally I saw how someone was able to tank him. I bought lots of tank gear and got myself to 1800 LOH, 62K HP, 600 resists, and about 4K armor but only 16K DPS and I was able to beat stage 2. However stage 3 Diablo does too much damage for the gear I had to tank. So finally I did a modified tank strategy. I tanked through the first 2 stages and then did the normal sniping and kiting for stage 3. It took forever to take out Diablo with only 16K DPS and ball lightning and caltrops as my primary damage dealer, but at least the pattern in stage 3 was much easier to understand than stage 2.
I probably died a couple hundred times on total before I got him. It may be cheaper to pay someone to do it for me, but there's nowhere near the same satisfaction...
I'm probably going to temporarily retire the DH and work on getting a Barb or Wiz to complete the game. I think it should be easier with a Barb since I won't be afraid of being one shotted...
I just finished D, but it was grouped and died constantly throughout the fight.....in fact just before he died, I got one shotted as well. Got the accomplishment, however it was very anti-climatic....:(
I will finish him solo just like you. I did want to note......BARBS KICK ***.....omg I have gotten mine up to act 3 vs Ghom, which my DH could not solo.... Barbs just chew up bosses, literally toe to toe, give them some LOH/leech and you literally just click the attack button. It's so nice to play a toon that doesnt get one-shotted just because they stood a little too close to a stray fireball or poison blast. I have had no boss difficulties with my barb........mind you he hits mobs like he was using a wet noodle and paper bag as weapons, but he eventually gets the job done.
Barbarians are ridiculously powerful, way better than a DH. I just finished Inferno with a Barb (Acts 2-4) in about a week after the DH using less than 2M of gear from the AH plus 4 items that the DH found. I used a 781 DPS spear (143 Str, 271 Vit) as my main weapon and had a 559 DPS axe with 179 Vit and 769 LOH as an alternate when dealing with certain bosses including Diablo. I was too cheap to purchase better weapons although that would be the obvious place to upgrade next. I used a 1H and shield and concentrated on going all out defense with my skills and gear. I normally ran with 22K DPS, but dropped down to 10K DPS when fighting Ghom and Diablo.
Ghom and Rakanoth gave me some trouble, killing me about 6-10 times each, but I got Diablo on the 1st try (with a 559 DPS weapon!). All the other bosses were relatively easy. I steamrolled act 2 and did die a number of times to elite packs in Acts 3-4, but far less than the DH with less than 1/10 the money spent. It was slower killing elite packs and bosses, but a lot safer compared to when I used the DH.
To be fair, the 4 found pieces that I used were generally pretty nice and I did have a Blackthorne's Breeches and Medal that I swapped in when I needed LOH. Still, there's no doubt that it's significantly cheaper and easier for a Barb to beat the game, at least for me.
To my knowledge, no one has completed the game on Hardcore as a Demon Hunter solo. Quite a few have done it grouped up though.
I remember when people complained about how overpowered the Demon Hunter was, and how the Barbarian was the weakest character in the game. This was within a few weeks after release. Oh how things have changed.