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Poison in Diablo II has two characteristics: how much damage the poison does (per second) and how long the poison lasts. Because of these dual characteristics, when two poison based attacks stack up both characteristics add up. As a result, some very interesting things happen.

Recently, Blizzard changed several things which make this particular phenomenon extremely interesting. It is now possible for any character to do over 200,000 points of damage with one attack. Yes, you can now theoretically kill Diablo in one hit on hell difficulty. As a side note, being poisoned turns off monster healing. A poison mod with a long enough timer is better than "prevent monster heal"!

There are several items that really make these numbers stack up quickly. First of all, it is possible to get one or two poison mods on each of the various charms. The best of the batch would be the Pestilent Small Charm of Anthrax. Pestilent adds 24 poison damage over 2 seconds and Anthrax adds another 10 over 2s. Remember, the two items add separately, so that the resulting charm adds 68 points of poison damage over 4 seconds. Since you could theoretically carry 40 of these things, that adds up to be 108,800 damage over 160s. That's 680 points of poison damage/second for just under three minutes.

Obviously, that's extremely skewed since the odds of getting just one of those charms is small. The odds of stacking 40 of them is ridiculous. But even the average joe can get ahold of perfect emeralds. And anybody can choose to make an Assassin with the Venom skill. Lets take a look at those next.

Lots of people have been talking about perfect emeralds. While the Pestilent Small Charm of Anthrax adds 17 points of poison damage/second, perfect emeralds add 29. What's more, in many weapons you can stack up to 6! For example, a military pick or a crystal sword can both have 6 gems and they have the advantage of being one handed weapons as well. Lets take a look at what a 6 perfect emerald weapon can do.

The exact damage a perfect emerald does is 300 * 25 / 256, or 29.296875 points of poison damage/second. It has a duration of one second. Ok, if you have 6 of them, they do 300 * 25 / 256 * 6 or 175.78125 points of poison damage/second. At this point, however, they have a duration of 6 seconds. The total poison damage from one hit would be 1054.6875 points of damage. Hardly something to shake a stick at. (Well, ok, but it'd have to be a BIG stick.)

But a character can also take this up a notch by becoming an Assassin. The Assassin has a skill in the shadow tree called Venom. At level 20 this skill does 375-415 points of damage over 2 seconds, or an average of 197.5 damage/second. Now, what if we put that 6 perfect emerald weapon into the hands of an assassin using venom? Well, the damage becomes 373.28125 points of poison damage/second. Total damage? 2986.25 over 8 seconds.

There are some caveats to this, however. Whenever a monster is hit with a second poison attack, it just resets the length counter. This means that additional attacks on the same monster won't have significant effect.

For most people, combat is really about how fast you do damage (or damage/second). Poison is a great way to really start to move faster. For example, if you have an amazon, have a 6 perfect emerald bow that you can weapon switch to. Multishot a few rounds of that out and then switch to your primary attack. You will be doing 175 points of poison damage each second in addition to whatever else you can pump out. Similarly, I think pretty much all assassin characters ought to have a weapon switch to a 6 perfect emerald weapon with the venom bonus. 373 points of poison damage/second makes a nice primary attack even into hell mode, and if you switch out to a high damage claw after the first poison hit, you can easily bring that up into the 700+ or higher damage/second category.

I should mention that the Necromancer has a similar skill to Venom that can be used called Poison Dagger. The problem with this skill is that it requires a dagger, which means you can only put 3 Perfect Emeralds into it. Theoretically it is possible to find an Artificer's Kris of Anthrax which will give you the three Perfect Emeralds plus an additional 13-25 points of poison damage over 2 seconds, but don't count on it, you'll probably just be stuck with a 3 perfect emerald kris. This isn't a bad skill since poison dagger does give a +% to hit, but the problem is that the poison damage from poison dagger doesn't actually make up for the loss of the other three perfect emeralds until approximately level 28. Yes, that means a level 20 Poison Dagger and at least 8 levels of +skills items. On the positive side, however, necromancers can use Shrunken Heads. The best shrunken head available adds 20-50 damage over 4 seconds. Don't get too excited though. This just means that you only have to get Poison Dagger to level 27 to make up for those missing emeralds. Overall, even poison based Necromancers should ignore Poison Dagger and get a decent 6 socket weapon for perfect emeralds.

The question comes up: what is the best setup for a Poison based character? Well, basically as much poison stuff as you can find, right? In terms of damage/second very little adds anything near as much as a perfect emerald in a weapon, but everything else adds significantly to the length of the poison, which helps, too. Obviously you have to balance in terms of playability, but to make a total gung-ho poison character, here's my list:

Poison Character:
Weapon: 6 Perfect Emeralds in a Military Pick or Long Battle Bow
Armor: Venom Ward
Shield: Tiamat's Rebuke (if using the military pick)
Belt: Snakecord
Boots: Any
Helm: A Septic Circlet of Pestilence (or a rare that has those mods)
Gloves: Venom Grip
Amulet: Atma's Scarab
Rings: Rare ring with Blight Mod

Poison Assassin:
As the normal recommendations except:
Helm: A Shadow Circlet of Pestilence (or a rare that has those mods)
Amulet: A Shadow Amulet of Blight (or a rare that has those mods)
Rings: Either of the +1 skill levels rings (Stone of Jordan, Bul-Kathos' Wedding Band)

Poison Necromancer:
As the normal recommendations except:
Shield: A Shrunken Head with the Anthrax Mod

Of course, get as many charms with poison (and +shadow skills for the assassin) as possible. Last but not least, the maximum theoretical poison damage you can do is (from the Poison Assassin gear):

This combination produces the highest poison damage/second I can come up with. What's more, over the length of its duration it does 225120 points of damage. I don't have the statistics for Diablo in the expansion, but this would have finished off the Diablo 2 Diablo in 62 seconds on hell difficulty. Hit him once, go get a drink, come back with an additional 3.5 million exp....
On a final note, please do not complain if you create a poison assassin and Blizzard nerfs the way poison adds up. Personally, I'd like to recommend that they do so the same way they handled Leech, Freezing, etc. and reduce the poison length by 1/2 in nightmare and 3/4 in hell.

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