Those very familiar with these skills might still find some useful information in the Comparison section, but the Overview might give you a bit of useful information as well (for example, I did some frame by frame analysis on Zombie Bears and calculated as precisely as possible the area of effect and range of all four skills.) There are two images in the Comparision section showing how the ranges and area of effects compare to each other.
So I thought perhaps when these posts come up, I could try to direct people to this post where hopefully their questions are answered.
Caveat - this is how I understand the skills to work from reading detailed posts by Nubtro, Wachati, PaulNg, Surijak, Skywalker, heyguyslol, etc. If anything in this post is incorrect, by all means let me know and I'll update it.
Each cast of Zombie Bears summons three zombie bears. Each bear does 236% weapon damage as poison.
First bear is summoned almost immediately in the middle, followed by a bear on the right of the player about .4 seconds later, followed by a bear on the left of the player about .4 seconds later.
The skill can just be held down and each wave will cast immediately after the first. As your attack speed increases, additional waves will tend to come out before the left and right bears have completed, resulting in a front loaded set of bears in the middle with a trailing wake of a left and right bear after you are done.
This techincally is not a channeled spell, but it behaves like one that has a mana cost of 140/sec multiplied by your attack speed.
A very important trick to zombie bears is that there are two ways to cast it. The standard way that produces the wave described above, and a way to cast them in a straight line by casting with your back against a wall. The "Zombie Bears Line" has a much greater range, but much smaller area of effect. The idea is that when there are few monsters, you cast the bears in a line so that all the bears strike the same monster, greatly increasing the damage done to a single monster (when done correctly it is triple the damage.)
More details here:
Pros - Massive range and area of effect, great damage
Cons - High mana costs
Cloud of Bats
Cloud of Bats is a channeled spell that summons a cloud of bats surrounding the player that ramps up damage to a maximum of 1001% weapon damage as fire.
The ramp up time is always 5 seconds.
The skill costs 221 mana to cast, with another 66 mana/sec to channel. You will always pay at least half a channel cost, though. This means stopping and recasting Firebats is very expensive (254 with no reduction gear per click of the spell), so you really want to hold it down. Also if you stop and restart, your ramp up time resets and you will need the full 5 seconds to get back to maximum damage.
But what a maximum damage that is - no other single spell comes close. Unfortunately, this damage comes with a price - the range is very small, and the initial casting cost is very high. This also means that many monster affixes can prove a serious challenge if they force you to either reposition and/or recast often.
More details here:
Pros - Massive damage at full ramp up
Cons - Range, recast mana cost
Plague bats is channeled spell that summons a large group of plague bats in front of the player in a cone at a maximum damage of 578% weapon damage as poison. This is another firebats rune but behaves completely different than Cloud of Bats except in it's mana cost, which is identical.
A very important point to Plague bats is that it is a damage over time. This means the optimal way to use it is to cast the spell on some monsters, then move to another set of monsters and let the damage over time kill the first set. In other words, you generally do not just hold the button down on the same group of monsters until they are dead.
Plague bats does its damage over time in stacks. Each stack will do 578% weapon damage over 5 seconds, scaled by attack speed (5 seconds / attack speed.) This means that at 1 APS, each stack will take the full 5 seconds to deal its damage, at 2 APS, it will take 2.5 seconds, at 3 APS it will take 1.67 seconds and so on.
The amount of time you need to hit a monster until it has its 5 stacks is based on your attack speed as well. The higher your attack speed, the less time you need to hit a monster before it will have the 5 full stacks. This is important because generally for optimal use, you want to hit a monster, get him to 5 stacks, then move on to the next, then move back to reapply the stacks as they begin to wear off. The amount of time before your maximum stacks is reached is half the time of the DOT (ie, 5 seconds/ attack speed / 2.) So at 1 APS, it takes 2.5 seconds to reach maximum stacks, at 2 APS, it takes 1.25 seconds, at 3 APS it takes .625 seconds, and so on.
As mentioned, the mana costs on this skill are the same as Cloud of Bats since they are both Firebats runes. So everything about recasting and repositioning applies to Plague Bats the same as it does for Cloud of Bats.
One other note about the DOT. For life sustain it has its pros and cons. A positive is that you continue to gain life from opponents you are no longer hitting, so even if you are forced to retreat, you will still be gaining life. A negative (and this can take some getting used to) is that since the damage has a slow build up, if you get swarmed you can die before your life sustain can fully kick in. This can be avoided by using walls, and carefully planning your soul harvest and spirit walks to avoid these situations (or using a skorn to double your life steal), but it is a danger nonetheless.
More details here:
Pros - Great range and good damage. The DOT makes it much easier to kite harder monsters
Cons - Slow initial life sustain, recast mana cost
Zero Dog is a unique build created by using 3 (sometimes 4) items to reduce the summon time of zombie dogs to zero, then using sacrifice to blow them up for great AOE damage. Since the summon time is zero, the speed at which you can blow dogs up is limited by only your attack speed. Each sacrificed dog does 275% weapon damage as physical in a 12 yard radius.
One of the unique properties of zero dog is that the dogs will leave behind health globes. This will cause your Gruesome Feast to always be at maximum stack for a huge damage boost. In addition, any other Witch Doctor in the party will also have maximum Gruesome Feast and will have a huge boost to their effective mana regen.
The build also allows for easy kiting as the summoned dogs will charge their targets allowing you to move out of harms way if need be.
Unfortunately, the negatives of a zero dog build come in its flexibility. To truly be effective, you really need to use three specific passives (Gruesome Feast, Zombie Handler, and Tribal Rites), and you must use both Summon Zombie Dogs and Sacrifice to do damage (taking away a skill slot.) In addition, to get the reduction to zero, you need three specific pieces of gear. There are some variations to this, but for the most part this is true.
Pros - Massive health globes, great damage, large area of effect and range, easy to kite
Cons - Restrictive build and gear
More details here:
100k weapon damage at 1 APS, 2 APS, 3 APS
1. Cloud of Bats (full ramp up, takes 5 seconds) - 1M/sec, 2M/sec, 3M/sec
2. Zombie Bears - 708k/sec, 1.4M/sec, 2.1M/sec
3. Plague Bats (5 stacks) - 578k/sec, 1.15M/sec, 1.7M/sec
4. Zero Dog - 577k/sec, 1.1M/sec, 1.7M/sec
Notes on damage:
These numbers are completely unbuffed.
Zero Dog typically has a full five stacks of gruesome feast and a constant 20% boost from provoke the pack, which isn't reflected.
Most other builds using the other skills will also use gruesome feast, so they will have stacks as well, just typically not the full 5.
I didn't know how to really account for those so I left them off, but I think this does paint Zero Dog in a worse light damage-wise than it really should be.
On the flip side, Zero Dogs requires two skills to deal its damage, so the other skills could potentially have one more damage buffing skill.
1. Zombie Bears Line - 55 yards
2. Zombie Bears Normal - 44 yards (30 yards forward, 14 yards behind)
3. Plague Bats - 30 yards
4. Zero Dog - 0 to 22 yards (can technically be as high as you need it to be, as you can let the dogs move before blowing them up.)
5. Cloud of Bats - 8 yards
Area of Effect
1. Zombie Bears Normal - 968 sq yds
2. Zero Dog - 450 to 1350 sq yds
3. Zombie Bears Line - 440 sq yds
4. Plague Bats - 210 sq yds
5. Cloud of Bats - 201 sq yds
Notes on area of effect:
The dogs summoned from zero dog appear in a random place somewhere between your location and ten yards, so the area of effect shows a range.
By the nature of the skill, Plague Bats is meant to be moved from side to side to apply the DoT to as many monsters as possible, so in practice the area of effect ends up being much larger. 210 yards is about the area of effect using the skill aimed at a fixed point.
Pictures are worth a thousand words:
1. Zero Dog - 0 (technically it costs mana to summon the dogs, but your regen and gruesome feast far exceed that.)
2. Plague Bats - 221 initial cost, 66*APS/sec
3. Cloud of Bats - 221 initial cost, 66*APS/sec
4. Zombie Bears - 140*APS/sec
Notes on mana cost:
Firebats reduction gear isn't what you'd expect:
Zombie bears reduction gear works as expected
Hopefully this has helped some folks new to the witch doctor class, or will just provide a nice consolidated comparison of the four major damage dealing skills in one place.
Thanks for reading!