An extensive guide on Chaos-DoT Spells ft. ED, Bane & Co [3.14 rdy]

1.1: I like purple.

1.2: It starts here and is mentioned several times throughout the guide, but the increased chaos damage taken from Withered stacks additively with the increased damage over time taken from Despair. So while Withered remains one of the strongest ways to scale chaos damage over time, it provides a bonus closer to 70% (72% with level 20 Despair, but that does not account for quality, curse effect, and curse effect on bosses). I find repeating the "90% more" to be slightly misleading.

Something else that seems missing for me, although it is admittedly not in the same part of the tree as most of the chaos nodes, is Spiritual Aid. This opens up various clusters on the tree and some stats on gear to benefit all forms of damage. I do not know about the current state of CDoTM nodes, but when it was new, it was very relevant to scaling chaos builds. In Blight, and possibly later if that part of Blight becomes a core mechanic, it can also be annointed if it is too far out of the way.

I do not know if or when it was changed, but the +2 to level of socketed support gems can be crafted on staves as well. It's possible that using a bow makes it easier to roll the other gem level mods due to a smaller mod pool. For high-budget builds, a staff with useful non-crafted affixes and the relevant gem mods is something that should be considered.

Staves also have access to Fortify in theory, although Leap Slam would be too slow as a useful movement skill. You could however use something like a Frenzy - Faster Attacks - Fortify setup, which incidentally would build / maintain Frenzy charges whenever you get your Fortify at a reasonable attack speed.

As I understand it, Soulrend will only leech from hits, whereas Essence Drain regenerates based on DoT, is that correct?

Because the hits of Soulrend are not scaled that much, this should usually cause ED to recover more overall, although it might need to be spread with Contagion first before reaching a level comparable with Soulrend piercing through a whole pack.

Soulrend: While you do not go into detail here, I believe that this is where investment into skill effect duration comes into play to a considerable extent. Even without extreme investment, it should be possible to reach roughly 100% uptime including some room for movement.

Blight CwC Soulrend: This is where I'm coming back to staves. Shaper staves can have the CwC support as a prefix. This would block out either one of the gem level mods or the CDoTM mod, but another support gem slot might be useful. Additionally, you could run a 6-link ED in the chest, that you do not have to cast often to maintain its full uptime.

Blight: Imo this section is missing a comment on how packs will die with the other skills before Blight reaches the point at which the dps has an advantage over the other skills. Blight is almost exclusively fit for single target. It can be used with totems as an alternative to Wither that also deals some damage, but usually the damage in that setup will not be very high.

Mistake in the cast speed calculation: The base cast speed are 3.33 per second, and while 50% cast speed does not grant 2 additional casts per second, it would be quite wrong to describe the 1.67 casts putting it at 5 casts per second total as only one cast per second. 30% increased cast speed will actually result in one additional cast per second, and I believe you should accurately represent the efficiency of investment into cast speed at this point.

It is a shame that Desecrate cannot be efficiently used offensively, and I hope that they buff its damage at some point. It would be nice to have another addition to the various ways of dealing chaos AoEs we have now.

Withered: Again the 90% more damage fallacy, and you used "your" instead of "you're". You did mention that you were not a native speaker, but neither am I, and this does bother me a bit. It is not crucial to this guide, but it would be nice if you could correct that the next time you edit it.

Efficacy: While I relied on PoB for most of my gem choices, and Efficacy was always up there, it surprised me that the two more mods actually worked multiplicatively. Many more mods on skills and support gems work additively with each other, though I suppose that those also actually affect the same stat, whereas Efficacy clearly affects two different stats. The skill effect duration is a very important aspect to both Soulrend and Blight imo.

Empower: I find the math to be a bit fuzzy, and from my observation of skill scalings, it can change quite a bit especially on higher levels. Just recently I did a bit of research on ED, which scales rather consistently until level 30, then falls off sharply. I strongly advise anyone to test setups using Empower in PoB before investing into it or an item supporting it.

And even until level 30, ED only scales for about 24% for two levels, which would be equivalent to around 11% per level, which is much lower than the 15% you advertise. I think 10% per level is a better rule of the thumb and more accurate to most skills.

I also believe that the comment on using it with Bane should include a statement that Enhance will be much more effective if Bane is used for curses rather than as a main damage skill.

Arcane Surge: A strong buff to spell damage and cast speed, that you should almost always include somewhere, although not necessarily on a high level in your main setup. Works especially well with movement skills, but could also be socketed with Bane if you have a slot.

If you build around it just a little bit, it should also be no problem to maintain a high level Arcane Surge on Soulrend.

Another very important thing to mention is that Arcane Surge benefits from skill effect duration. So if you have a skill effect duration cluster with 45% on the tree and use Efficacy and Malevolence, you suddenly have 7.2 seconds to spend 400 mana, which translates to about 56 mana per second, which in turn shouldn't be that hard to hit with soulrend and 5 supports.

In a Soulrend build, rather than considering the uptime which will almost definitely be very high (and you can slightly reduce the level of the gem to make it 100% if necessary), it should be compared with using a lower level Arcane Surge for the buff in a different link, and the investment of using that link in a movement / utility setup for Arcane Surge rather than anything else.

As always, for precise numbers, use PoB.

Enhance: This is slightly unrelated as my character will not be focusing on dealing damage, but I am planning on a curse support build in which Bane and Enhance in several links will play a very large role. It should be clear that Enhance is the best support for Bane if Bane is not supposed to deal a significant amount of damage for that build.

While I agree with this obvious choice of curses, I think you should explain their benefits in mechanics in greater detail, which by the way would also include the diminishing scaling of Withered, as well as a description of how curse effectiveness on bosses affects buff expiration with Temporal Chains.

When I plan builds, I use PoB for such numbers, but I believe it would be appropriate to have a ballpark calculation with example values, especially considering you occasionally use that number for your explanation of skill durations.

Additionally, Punishment can be considered a niche option to increase the speed of movement attack skills / reduce the time spent for Frenzy (in the example utility link I mentioned earlier, which would also replace the curse slot of Poacher's Mark). Particularly relevant for Blight builds that have a very short range and are thus more likely to be hit by melee attacks.

Vixen's Entrapment: I have read someone else's comment about it before stating that all curses in it would be cast whenever a curse skill is used, is that true? Conventionally, triggers like this would only trigger a single skill per triggering event, and the wording is "Trigger socketed curse skill" as opposed to "skills".

Curse on Hit: I believe Mark of Submission deserves an honorable mention, especially with Profane Bloom. Because it applies to all hits, Profane Bloom will apply the curses socketed in Mark of Submission, and with enough scaling for chaos damage (this does not benefit from bonuses to spell damage or damage over time, but it does benefit from increases to minion damage if you have Spiritual Aid) this explosion can chain through packs. This is the same type of explosion as the one from Obliteration, so you could use a dual wield setup of those for even faster pack clearing (instant death is faster than a DoT that kills everything almost instantly; 300IQ; may cause performance issues due to simultaneous explosions). It works well if you also scale AoE for Blight or Contagion.

Blasphemy: It should be noted that the various ways to use Blasphemy should be used separately. Because quality on Blasphemy increases the effect of the curse, it is quite important to use the actual gem and possibly Enhance and increased Area of Effect if you actually have a corresponding Impresence, whereas Heretic's Veil is good if you do not, and either Blood Magic or Prism Guardian can be used to run LL for PA with Blasphemy. Prism Guardian in particular could of course also be used for Malevolence and Zealotry, while the actual Blasphemies are socketed in a Heretic's Veil. However using two of those options for the same purpose is usually not efficient.

As someone else mentioned, Withering Step is a very important skill that needs to be mentioned in this section. With the right enchantment, it can apply 9 stacks of Wither right away, just from entering the general vicinity of an enemy, and it provides a lot of movement speed as well as some dodge / spell dodge.

You have mentioned this in the patch changes at start as well, but due to the Occultist's ES nodes being a lot weaker than they used to be, Withering Presence is definitely worth a second look now, especially in combination with Withering Step.

Spectral Spirits: They seem to have a base accuracy of 1400, which equates an 87% hit chance against level 84 enemies (Shaper's Realm), and they seem to have an attack speed of 2.46. So it would apply approximately 3 * 2.46 * 1.54 * 0.87 * 0.25 = 2.47 Wither stacks per second, which would last another 3.48 seconds for an average of 8.6 Wither stacks applied this way, divided by (1 - slower expiry from Temporal Chains) for the effective average stacks. Maybe there is more that can be done with a 2-handed weapon, but considering the potential for two main skills with chaos DoTs, I cannot see how this would exceed that damage.

Alternatively, fast hitting spectres with Withering Touch might be more useful.

In either case, they might provide a bonus to damage if you spec into minion damage with Spiritual Aid. Using Spirit Offering would also convert more of their damage to chaos, which would make them benefit from your Despair.

This whole part also applies to section 8., but I did not know how to split it up in a way that would have made sense.

This is probably just leftover gear or you did not need the additional support gem slot for damage, but the body armour of your first build includes two copies of Efficacy.

Blight-Totems: I do not believe that you really need to bother with too many aura nodes, even if you do intend to run Purity of Elements.

Wither-Totems: Should include a paragraph mentioning that these can very easily be added with the Multiple Totems Support gem even if you have another totem setup already, because you do not care about damage for them, and if you only place two (i.e. with one placement), they will also not limit the other totems with lower totem limit.

While I do not have space for it in the tentative totem build that I threw together on the spot just to check it out, mines or traps could be used in order to deal additional damage despite using Ancestral Bond.

If 15 mines are placed, the Blastchain Mine Support gem provides 31% more damage. It would likely be used on conjunction with Minefield, because laying all those mines would take a long time without it, which, with the two nodes granting additional mines from the tree, would result in 61% more damage overall, which would be equivalent to two 27% more gems. So overall, it is not even an option to set up a particularly powerful ED while the previous one is still ticking, because other support gems will be stronger.

I have also checked the Saboteur Ascendency, and since I last played it, it was nerfed so far, that it basically has nothing left benefiting chaos DoT builds. There is close to no point to even spend all 8 Ascendency points. A Deadeye would work better with a regular Soulrend build than Saboteur with chaos DoT traps or mines.