Heres a general guide to the diablo fight that I've put together from past experiances. Now, party members will vary and builds in the party will vary but i`ll try to add all builds in and what kinda skills etc. group members should be using.

We'll start with the basics. Diablo's attacks come in a variety of forms. Volcano, Flame Wave (big version of druids firestorm), a fire version of the sorcs Frozen Orb, his own version of multishot Fireball, his Lightning spray attack, spawns bone cages, weaken, Lower resist, Iron Maiden, amp damage and normal melee attacks. You'll notice that most of his attacks are mainly a combination of small hits rolled into one.

Damage reduced by xx and magic damage reduced by xx will go a long way here, along with maxed lightning and fire resist. absorbs are extremely usefull in this fight too (lightning and fire).

Expect to get caged with a volcano under you. Without teleport your gonna be in trouble if you get caged with a volcano under you and he uses Flame Wave. Thats when magic damage reduce and absorbs will really help. Get out of the cage as soon as you possibly can. (party members help others escape) Iron Maiden is managable on a melee build. Make sure you use single target attacks. Concentrate on a barb, Sacrafice/normal attack/Smite/ on a paladin, feral rage/maul/frostbite/fireclaws on a druid. You may get away with jab on a jabzon, any multiple target attack like zeal/fury is a problem as if he spawns a cage and iron maidens you, you will hit the cage, not leech from it, and take alot of damage. His lightning spray attack and flame wave are very dangerous, even without being caged. The lightning spray is half lightning half physical damage. PDR, MDR, Max light res, lightning absorb, and Dr% will pretty much negate the effects of this. For flame wave, fire absorbs, MDR and max fire res will take most of the sting out of it. His other attacks are not much to worry about.

Build Skills:
Paladins who can use resist auras should do that, Fire resist or salvation depending on what the other members need too. This will make the fight alot more easy paced and safer all round.
Druids should have oak up at all times. Beware Flame Wave popping your oak instantly so try to avoid using grizzly bear as if you cast it and oak dies right after, you have a long time to wait to cast oak again. Dire wolves are a better choice here imo. Single target attacks only
Barbarians should keep all members battle orders up. Single target attacks only, avoid WW unless your damage is very low and are using a crushing blow setup.
Assasins should be able to keep a shadow up and running as much as possible
Amazons keep decoy and valk up as much as possible
Sorceress' should be in all out attack mode. chant party members if you have it even if just for the ar bonus (only low counter causing skills. eg, not f orb/charged bolt)
Necromancer should keep the groups choice of curse up at all times amp/decrep/lower resist. keep casting blades, clay golem, iron golem and force golem

The Fight:
Chances are he will focus on one main member, if he focuses on you, keep running from side to side. He will use his lightning/phys attack alot and running from side to side, away from your team will mean they AND you will take next to no damage. Even if your not attacking, drawing his agro to you will make the fight alot smoother. When he uses flame wave, run to the side and attack from another angle. The less time your in these attacks the better. Have the necro cast a clay golem in between blades/curses/fire golem. This will slow him and reduce risk. Load your melee tanks up with crushing blow, the more the better. Losing alot of damage in place of crushing blow is fine. If there is more than 1 tank, take it in turns to hold him. He has a large area of effect so if you have one person taking the hits for 20 seconds then another taking the hits for 20 seconds you will half the amount of pots needed. If any member gets caged try to help them break the cage to minimise the risk of losing a player.

Follow those simple steps and your group should make it past without to much trouble. If you have no nec, get an amp wand and take 3 or 4 repair runes with you or get a weapon with ctc amp/decrep. (lawbringer is very good here) if you have no paladin put rubys in your shield and diamonds in your armour/helm if you can. Take a cube of reds and a cube of rejuvs. reds can heal your spare tank while the other is holding him. If you have no lifebuffs, wait.

If you find a fire shrine in there, dont use it untill diablo spawns. Get every member ready when you hit it and you will take a massive chunk of his life off.

Please add to this if you found something else usefull here or have any variations on this.

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is it my imagination or does he ALWAYS chase the zon in battles? I am serious, seems like when I play a zon at Diablo my main strategy is:

1. run around a wholoe lot while firing guided and tossing out decoys
2. let my party hit him while he is chasing me

I know it makes zero sense for the game to be coded that way, but I can't shake that feeling.

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People who live in cinder block houses can throw whatever they want.

Zon or Sin according to my highly unscientific research. Aka what I've noticed.

It might have something to do with the chars life, that he would target the weakest char?

I find the same thing with sorcs, from what i can think, there is a kinda general order he follows

from most followed
zon/sin
sorc
paly
nec
druid
barb

He obviously likes the boobies, I'm pretty sure he has chased my druid before in a fight when there have been sorcs/zons there for him. Once he picks a char to chase he seems to stick with it.

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My newest experience versus this overgrown fallen in normal:
Dragonclaw assassin lvl50 and necro around lvl46, the sin was me, and with my 1.4k life didnt had mayor issues taking him down pretty easy and fast, the life buffs arent that important vs this guy like many ppl say but the point is that our tactic was run around him 5 seconds or so and then attack him 10 seconds and repeat, and ofc keep him always amped, doesnt matter if i get hurt or not when im attacking him those 10 seconds i always start running again around him in circles for safety... its more like synchronized fight what we had, a small patch of pots near the fight was enough for this job also and yeah ofc do not forget that blades are necesary if u team up with a necro, they help a bunch.

It's any ranged action. A barb can be focused by diablo by just casting BO

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iz a secret

Always thought Diablo was a pretty pathetic act boss in all difficulties. He's just so one dimensional. A little fire absorbs and he pretty much tickles. I've also found his melee damage to be a joke. I think even Mephisto is harder than him pound for pound, and he doesn't even have moncurse.

didnt diablo cast too LOWER RESIST ?

he casts LR

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Mess with the best, die like the rest!!

He uses moncurse, which includes weaken, IM, amp, and LR.

cheers

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