[2.6] [Cheap/Beginner friendly] Essence Drain/Contagion life scion

The build revolves around those main spells:

Essence Drain: a projectile spell DOT, and Contagion is a DOT AOE spell.
Contagion: An AOE zone that is placed on enemies. it propagates Essence Drain.
Wither: A debuff that increases chaos damage taken, and reduces movement speed on enemies.

The basic gameplay is that Essence Drain can be applied to all enemies, thanks to Contagion spreading it.

When enemies die, their Contagion is also spread to other nearby enemies. You can basically wreak havoc on all enemies in an area with a contagious Essence Drain.

Wither makes the build even more powerful as it increases chaos damage taken, and slows enemies which is always nice.

High level skill tree – 120 points (level 96)

Most of the skill tree is oriented towards getting chaos damage/dot damage/projectile damage.

It contains a lot of life and mana, as it will be the only defence for the character, except for Mind over Matter, which will give us a flat 30% damage reduction taken from mana.

Alternative skill tree, slightly less life but lots more damage. - 121 points

Main
Essence Drain - Void Manipulation Support - Controlled Destruction - Rapid Decay - Pierce - (Slower Projectiles / Empower / Faster Casting)
This is your main attack, supported by links that will boost its damage


Spread
Contagion - Faster Casting - Increased Area of effect - (Increased Duration if you want, or use the slot for another gem)

Using contagion will spread your Essence Drain. It is quite a slow spell so Faster Casting is important here. Increased Area of effect is a nice added comfort.


Debuff
Wither - Spell Totem Support - Faster Casting

Wither on a spell totem will debuff enemies to make them slower and take more damage. You just have to place the totem and it will debuff enemies.

Curses
Blasphemy - Temporal Chains - (Vulnerability / Enfeeble) - (Enlighten optional)

Blasphemy transform curses into an aura around you.
Temporal Chains has multiple benefits: It makes enemies slower, but it also makes our dots last longer
Vulnerability increases damage taken from dots. Great source of damage for us. Alternatively you can use Enfeeble if you have trouble surviving.
Enlighten can be added optionally if you can afford it, to reduce the mana cost of those curses.

Alternative option with CWDT and Immortal Call:

Cast When Damage Taken - Temporal Chains - Enfeeble - Immortal Call

Minions
Summon Stone Golem - Minion Life Support - Animate Guardian / Minion and totem resistances

Animate Guardian can be equipped with uniques that give you buffs. If you can afford to get those uniques (not really expensive), your guardian will increase your damage output. (Section about that coming).
If you don't want to use Animate Guardian, just add Minion and totem resistances, or use that slot for whatever gem you want to add (vaal gem for example).

If you want more damage, you can use a flame golem.

Movement
Leap Slam - Faster Attacks - Fortify To get free Fortify
Or:
Whirling Blades - Faster Casting - Fortify
You will need to use daggers if you go that road, but it's a far better movement skill than leap slam.

Others
If you have free slots, here are some good options:

Clarity: Mana regen if you feel like you don't have enough
Herald of Ash (especially if you use the consuming dark dagger, more about that leter)
Vaal Haste - If you want a good damage burst vaal.

The stats you want to look for are:

- Maximum Life
- Elemental Resistances (to get your cap. The few nodes for elemental resistances in the tree should help get a head start on that)
- Chaos Damage
- Damage Over Time
- Spell Damage
- Projectile Damage
- Case Speed (Not necessary as you don't need to cast a lot, but if you feel your contagion/essence drain are slow...)
- Mana and mana regen are always nice, as our build uses mana to mitigate damage

The stats don't care about and that won't benefit you:

- Anything related to critical strikes (criticals are useless on dots as they only work for the projectile itself and not the damage over time)
- Anything related to charges as we don't use them

Animated Guardian

The Animated Guardian can become interesting if you gear it with the right items. Some items can give him auras that will apply to you and other players.
These items are also cheap to get, and you don't need good versions of them as it's not for your own gear.

If you do want to use animate guardian, I would advise to pick a minion life regen node in the passive tree. There is one accessible near Retribution in the tree.

Remember that if the guardian dies, its items are destroyed. so don't waste your items if your guardian isn't powerful enough. Playing with guardian is optional.

Useful uniques:

Dying Breath - Gives a +18% damage aura - Price Check
Leer Cast - Gives a +15% damage aura - Price Check
Zahndethus' Cassock - Gives tons of chaos resist to your guardian + drops consecrated ground on block that can heal you - Price Check

21 Points
The skill tree starts on the right side, quickly grabbing the most accessible chaos node, and continuing towards useful nodes in that direction.

You will be able to get Contagion, Essence Drain and Wither quite fast. In the meantime, playing with Fire trap and a spell like Spark is good enough.

As soon as you can, get Contagion, Essence Drain, Spell Totem and Wither. You can also get Void Manipulation during act 1, and you can have an Added Lightning Damage if you have a link to use (not great but better than nothing).

In act 2 you will get faster casting

40 Points
Here we get more chaos damage in the right of the tree, and a bit more survival. Then we start our path on the left of the tree.

Around act 4, you can unlock the Stone Golem, and the increased area of effect gem.

60 points
We start climbing the left of the tree, getting some more mana/regeneration. We take Mind over Matter, which will be a big source of our damage reduction (30% of damage taken from mana).
We also get the first important life nodes in the big life wheel.

Level 60 - 84 points
Here we grab more curse and chaos damage at the top of the tree, and also a useful defensive node on the right.

Level 80 - 104 points
Here we grab nodes at the left of the tree that are good for our survival and also area of effect, some life leech at the right of the tree, and a jewel socket.