Welcome to the guide exile. In this guide we are going to be examining just how Leech works in Path of Exile. Leech works in the same manner for Life, Mana and Energy Shield. Here we will focus mainly on Life leech as the prime example, and unlike in most other games, is quite the confusing mechanic. It has many moving parts, multiple attributes that can affect it and rules with each one of them! So let’s get right into breaking life leech down into some small instances.
How It Works
Life Leech works in the following manner:
- For every hit that deals damage, a #% of that damage will be returned to the life pool by means of a Leech Instance.
- That Leech Instance will replenish that #% of damage at a Leech Instance Rate of 2% of Maximum Life per Second back into your life pool. So leech instances can be thought out as dynamically sized buckets with regulated exit valves. You can fill the “bucket” with large or small amounts of leeched life, and then that life is slowly returned to your life by means of the Leech Instance Rate valve. We will discuss this later, but adjusting the Leech Instance Rate valve, also adjusts the amount of damage leeched! Along with this, each instance can have a different durations, since each hit can have a variable damage value, as seen between the larger and smaller buckets
- Leech Instances stack together simultaneously, until they reach a Total Leech Rate of 20% of Maximum Life per Second. By default, this is a maximum of 10 Leech instances!
- Once the Life pool is full, all Leech Instances will be dropped. Just like how Life Potions function!
Now, as we can see, the aforementioned Leech Instance #% Rate and Maximum #% Leech Rate are a function of your Maximum Life. This means that the more life you have, the faster your total raw leech per second is. However, the time it takes for your life to recover to full will remain the same, but will make it more powerful relative to flat incoming damage!
For example, a character with default leech and 10,000 life would be able to leech at a rate of 2,000 life per second. If we reduce his life to 5,000, then he would only be able to leech at a rate of 1,000 life per second. As you can see, the 10,000 life player not only has more life, but would be able to counter a 1,000 damage over time effect much easier!
Beyond the default values, Leech Instance #% Rate and Total #% Leech Rate can be modified! The two main stats that affect these respectively are: #% Increased/Reduced Life Leech per Second and +#% of Maximum Life per second to Maximum Life Leech Rate.
- #% Increased/Reduced Life Leech per Second will increase the Life Leech per Second of each Instance, along with the Amount of Life Recovered by each instance. (This relates back to the bucket analogy!) This is because the duration of each Leech Instance is set by the default 2% Life Leech per Second Instance Rate, before this modifier, as shown in this formula:
Leech Duration = (Heal Amount / (Max Health Pool * .02))
Ultimately, this modifier will act as a multiplier to your Leech Instance #% Rate & #% of Damage Leeched as Life!
For example, if you leech 5% of damage as life and you get a 50% increased Life Leech per Second modifier, then you would leech 7.5% of damage and heal for 3% of Maximum Life per second an instance!
Now, by default you will only be able to have 10 leech instances:
Instances = Total Leech Rate Cap / Leech Instance Rate Cap = 20% / 2%
= 10 Instances
Extra leech instances will be ignored. Increasing this stat will reduce the number of instances required to hit your maximum leech rate cap, and vise versa for reducing it. In our previous example, we would only require 8 instances to reach our Total Leech Rate Cap.
Increasing this stat is very useful for builds with slower and heavier hits, or small damage hits, as it will allow faster achievement of reaching your Maximum Leech Rate cap in fewer hits. Ultimately it allows all builds to get to their Total Leech Rate Cap much faster.
Modifiers for this stat can be found on the Passive Tree with General Attack Damage Leech Nodes, Weapon Nodes & Vaal Pact as well as Items such as Carnage Heart!
- +#% of Maximum Life per second to Maximum Life Leech Rate will raise the Total Life Leech Rate cap that the leech instances sum up to.
By default this is 20% of Maximum Life per Second. If you are to pick up +3% of Maximum Life per second to Maximum Life Leech Rate, then your Total #% Leech Rate would be 23% Maximum Life per Second.
This is the most powerful of the two stats to increase, as this is the upper bound of your leech rate and most builds will always hit this cap, creating all of their leech instances almost instantly, due to damage per second potential.
Modifiers for this stat can be found on the Passive Tree with Vitality Void & Vaal Pact as well as Items such as Shaped Amulets!
You can ultimately think of getting +#% of Maximum Life per second to Maximum Life Leech Rate as a conditional #% Life Regeneration Equivalent!
Now that we get how the basics work, let’s look at some other modifiers that can improve or change leech even more past these two stats!
This is one of the most powerful upgrades to leech that one can get, and is ultimately surnamed from the Duelist’s Slayer Ascendancy. Gained from The Slayer’s Brutal Fervour in which Life Leech Effects are NOT removed at Full Life. This can also be gained via the Scion’s Ascendant Slayer Mini-Ascendancy. This means that once Full Life is reached, Leech Instances will not be removed, and can still be generated! This is incredibly powerful as this more closely resembles how Life Regeneration functions (always on) and leech instances can last for extended periods of time, letting you roam around not attacking anything, whilst still leeching at full rate! This leech modification pairs very nicely with the next Keystone we will talk about.
Vaal Pact has gone through many changes through the years, and will probably go through more! For now, it Doubles your Life Leech per Second & Maximum Life Leech Rate, whilst removing all Life Regeneration. For a default character, this means you will have 4% Life Leech per Second per Instance and 40% Maximum Life Leech Rate. As previously mentioned, this works great with the Slayer Leech, as you are able to turn your Life Leech into a more stable Life Regeneration Effect as it goes through full life! For other builds, you will want to consider if you are able to manage without life regeneration, or if you have roughly 20% life regeneration already, you won’t be gaining much at all!
Ghost Reaver will apply all Life Leech effects to Energy Shield and no longer apply them to life. This includes the main two stats: #% Increased/Reduced Life Leech per Second and +#% of Maximum Life per second to Maximum Life Leech Rate, but does not include things such as the Slayer Leech.
Life & Energy Shield Recovery Rate
This stat can be found just as Life, Energy Shield or Combined on many different sources such as Elder Base Belts, Pantheons such as Soul of Arakaali & the Map Modifier: Of Smothering. This stat is a total multiplier to your final Maximum Recovery Rate stat (including Leech and Regeneration). For Example, this means that for a default character making use of the Soul of Arakaali that provides a 50% Increase when it procs, will move from a 20% Maximum Life Leech Rate, to a 30% Maximum Life Leech Rate (it also multiplies your Leech Instance Rates). That is incredibly powerful, and is quite easy to integrate into most builds! So keep an eye out for Increases to this Recovery Rate Modifier where you can get it. On the flip side, reductions such as the map modifier: Of Smothering are just as powerful in the opposite direction, so beware of this mod in high tier maps!
Ok, so that was all most definitely a data overload, so let us zoom out a bit. No not like that! Ok, let us take a step back and look at an example of Life Leech in action!
Let’s say that we have the following stats and deal the following damage per hit:
Leech: 5% of Damage Leeched as Life
The following will happen per hit:
We will create a Leech Instance calculated by:
Damage * #% Leech = 10,000 * 5% = 500 Life
500 Life will then be recovered at the Leech Rate per Second, which is 2% of Maximum Life per second by default, which is 100 Life per Second for this character. So for this hit, we will recover 500 Life in 5 seconds:
Leech Duration = (HealAmount / (MaxHealthPool * .02)) = (500 / (5000 * .02)) = 500/100
= 5 Seconds
Again, Leech Rates are functions of Maximum Life. This Leech Instance Rate can be increased by items that provide #% increased/reduced Life Leeched per second. So let’s say, for this example, we get items or a source that provides 100% increased Life Leeched per Second. Each Instance of Life leech will now recover at a maximum of:
5000 * .02 * 2 = 200 Life per Second
Our Leech duration will remain the same, we will just now recover 100% increased Life per Instance instead! So 1,000 Life for this example!
This now means we now need fewer Leech Instances than the base 10, to hit the base Maximum Life Leech Rate Cap of 20%. For our example, we will be able to have 1000 Life per Second combined from all of the Leech instances.
So we will have to hit 10,000 Damage 1 time per second at a minimum to reach & maintain that leech rate cap:
Maximum Life Leech Cap = 5000 * .2 = 1000 Maximum Life Leech per Second
Leech Instance = 200 Life Leeched per Second
Leech Instance Duration = 5 Seconds
Hits per Second: (1000 / (200 * 5)) = 1 Hit per Second
Even with our somewhat below average 2 hits per second we are able to greatly exceed our maximum Maximum Leech Rate cap, and end up dropping many excess Leech Instances. We have a possibility of fulfilling a 40% Life Leech Recovery Rate:
Leech Instances = Hits per Second * Instance Duration = 2 * 5
= 10 Possible Leech Instances
Total Life Leech Rate = Leech Instances * Life Leech Rate per Second
= 10 * 4 = 40% Possible Total Life Leech Rate
This means, theoretically, we could reach an 40% Maximum Life Leech Rate if we are to attack for 5 seconds without failure. So to take full advantage of this, we would need to increase our Maximum Life Leech Rate from 20% to 40%.
This could be done really simply by means of Vaal Pact, doubling our Life Leech Rate! However, this will also double our Life Leeched per Second, meaning that we will have 8% Life Leeched per Second for each instance, increasing our theoretical Maximum Life Leech Rate again! So for this example we will not do that.
Total Life Leech Rate = Leech Instances * Life Leech Rate per Second
= 10 * 8 = 80% Possible Total Life Leech Rate
Instead, to increase it further, we could make use of nodes such as Hematophagy & Vitality Void to bring a total of +9% of Maximum Life per second to Maximum Life Leech Rate. There are a few more sources for +#% of Maximum Life per second to Maximum Life Leech Rate, but I will leave you to explore that further, as this is just an example to explore how the modifiers interact together! In final, we will have:
4% Maximum Life Leeched per second per Instance
29% Maximum Life Leech Rate!
So as a take away, for Life or Energy Shield Leech, you will only want to be investing just enough #% of Damage Leeched as Life, along with #% Increased Life Leeched per Second to hit your Maximum Leech Rate within a small number of hits. This is of course variable per build, depending on the damage and attack speed, but for the most part you will only really need to worry about getting a few #% of Damage Leeched as Life and whatever #% Increased Life Leeched per Second you get along with that. It is more about picking up as much +#% of Maximum Life per second to Maximum Life Leech Rate as you can get, to move your upper bound on leech up, as the damage potential of builds hit this cap very easily. As always, thanks for watching and I’ll see you in the next one Exile.