Warlock is an unusual hero - with some unique skills. While a good support hero during the laning phase, his true potential can only be unlocked by fighting with his teammates.
He's very potent at early harassment, especially against evasive heroes like Weaver or Windrunner who can avoid auto-attacks.
He suits players with good positioning and tactical sense, who enjoy co-ordinating with their team. Hes a poor choice if you like to farm and want a big number in your kills column.
+ Good starting strength and growth
+ Good starting intelligence and growth
+ Excellent team fight skills
+ Doesnt need a lot of expensive items to be effective
+ Fast attack animation and projectile speed
+ Long range initiation
+ Good babysitter
- Poor starting agility and growth
- Long cooldown time on spells
- Lacks ability to inflict much damage by himself
- Long cooldown on ultimate
- Ultimate is his only stun
- No escape mechanism
Fatal Bonds is an excellent skill which holds its value throughout the course of the game. Every enemy linked by the bonds will take 20% of the damage suffered by the others, making it absolutely devastating when combined with big AOE nukes from your team.
During the laning phase, you can use this spell to harass enemy heroes, and to push the lane out where required. Its a little expensive for its effectiveness at this point, but it does tend to make enemy heroes more passive.
During ganks you should attempt to bond together enemy heroes whenever possible, or just to creeps if necessary. This extra damage can make the difference between getting a kill or not, as the bond has no range limitation. It also makes it difficult for enemy heroes to juke, as the bond will show where they are.
During team fights you should always attempt to link the enemy heroes as quickly as possible, a 20+% damage boost is massive, and can also kill off enemy heroes who attempt to flee the fight on low health. Bonds is your main damage skill and scales extremely well.
Fatal Bonds is your only real farming spell you receive the gold for any creep killed by the fatal bonds damage rather than a direct attack from another creep or player.
Bonds works by a rare form of damage known as "HP Removal" - this subtracts damage directly from a player and is extremely difficult to block or reduce, however it doesn't trigger an "attack effect" on the player, so does not stop abilities like Blink Dagger cooldown.
Shadow Word is your Heal and Damage spell depending on whether you cast it on a friend or enemy. I cant really call it a Nuke as it takes 9 seconds to inflict all of its damage :-).
Shadow Word is useful early game for healing yourself or your lane partner, slowly building the HP back up. The only issue is that it takes time to do this, so prove ineffective against big burst damage.
Since I originally wrote this guide, it has been buffed to be much more effective at level 1, and a little more effective at the higher levels too. This makes it viable at any point in the early game, but I think the sweet spot is still level 2.
You can also use it to harass too, although its unlikely to get you a kill unless they're already on very low health and trying to retreat. Later on in the game, you can use it to heal up your team and weaken enemies, but is a low priority compared to your other skills in a team fight.
A very powerful spell that is practically a 2nd ultimate in terms of its AOE, cooldown (50 seconds!) and potential effect. It also has to be channelled, which means it should usually be cast 3rd after Fatal Bonds and Rain of Chaos in a team fight.
Upheaval has a very large area, but it takes time for it to really build up effectiveness. Depending on the level of the spell, every second you cast it increases the amount of slow by 7/14/21/28%, up to a maximum of 81%. Hence it takes 12/6/4/3 seconds to reach maximum effect. Enemy heroes are also slowed for 3 seconds after they leave the AOE of Upheaval.
Upheaval can really mess up enemy teams who pick too many melee heroes, although heroes with either a blink ability or dagger are much less effected. You can also use it for early ganks and escapes its a little impractical, but can be surprising effective.
This is Warlocks showpiece skill, combining a massive AOE stun with damage and free minion(s). This is a really great initiation spell, as you can cast it from long range, allowing you to stay out of trouble while opening the door for your team.
Rain of Chaos has a 1 second stun that will bypass BKBs, and inflicts 100 damage at all levels. It will also summon an Infernal, one of the strongest minions in the game, packing a radiance-like effect, plus good damage and hit points. Be aware that enemy heroes can claim 100 gold for last hitting it.
The Infernal is great for attacking enemy heroes while youre busy channelling Upheaval, and can also be used for farming and tower pushing afterwards. Buying an Aghanims Scepter means RoC will summon 2 Infernals instead of one, but their hp and damage are reduced by 25%. With a Refresher Orb you could potentially have 4 Infernals at once :-)
On the downside, Rain has a long cooldown time (nearly 3 minutes) and should not be wasted. Early game, the ideal time to use it would be to initiate on the enemy lane heroes, and then push straight on to their unguarded tower. Later on you should only really be using it for team fights, and the Gollum does lose some of his impact.
Your combo was made for team fights ideally it should go:
1) Fatal Bonds
2) Rain of Chaos
However, sometimes the situation requires you to cast RoC first to get the stun, then follow up with Fatal Bonds and upheaval.
If you have a Refresher Orb, make sure to cast RoC again before launching in to Upheaval.
Warlocks biggest issue is mana - his skills are expensive to cast, and although his right click is good for last hitting/denying, it is poor in terms of DPS. Early game is about managing these costs until you can some additional regeneration, usually Arcane Boots and plenty of levels will do the trick.
You are definitely a support hero, and should always be prepared to help your team out by buying items such as a Courier or Wards, plus utility items later on. In most lane setups you should allow your partner to farm, concentrating on denial and harassment. You can grab some farm when you get the chance, but you should concentrate far more on teamfights and pushes.
Once you've solved your initial mana problems, you should concentrate next on utility items depending on who else is on your team. If there are heroes already doing this, you may be able to go straight for your luxury items.
Obviously everyone has their own favourites, but personally I like this:
2 x Clarity (100)
2 x GG Branches (106)
Courier and Wards (300)
As a ranged support with a good attack animation, you can generally stay out of harassment range, allowing you to heal yourself or your carry as necessary with Shadow Word. The branches provide a cheap boost to your stats, and can be used for your mekanism later on.
Depending on the way the game plays out, and your slow farming speed you wont necessarily get the chance to buy all of these items, but here are some of the options.
Unless someone else on your team (e.g. Lich, Dazzle) has already got a Mek, or its too late in the game for it to be effective, you should be aiming to get one for your team. Its regen and auras are useful for you, and you should be at all the team fights when its needed.
Drum of Endurance:
Another good team item, it boosts speed and attack speed for you and nearby allies, plus providing some nice stats gains. Its a solid item choice if your team doesnt already have one.
Veil of Discord:
A good item for Warlock, it adds to his staying power, mana pool and the damage potential of your team. A good buy if your team has some decent nuking power.
Due to your support status, relatively poor farming speed, and that you might have been buying wards and dust all game you may find expensive items difficult to acquire. If you can afford one, its important to get the choice right:
A very solid item; gives you a lot of stats and further improves your Ultimate. However, the dual golems are not likely to be that effective by the time you acquire this item, and you might want to consider a Refresher instead.
An extremely expensive item, but it adds a lot of intelligence/mana related stats, and gives you the ability to instantly cooldown your skills. This is very, very useful for Warlock, but the cost makes it difficult to be able to afford one.
Warlock benefits from the extra strength and intelligence provided, and can make good use of the minions. However, he may struggle to afford the upgrades that really benefit this item such as invisible hero detection. Specific situations only.
Scythe of Vyse:
Or Sheepstick, this item is very powerful, but expensive. It adds a lot of power to your right-click, and gives you an extra hex ability. However, neither of these can be used while channelling upheaval. Ideally there will be someone else on your team to carry this instead, but in specific situations (e.g. against the likes of Storm Spirit, Anti-mage etc) it may be vital.
At just over half the price of a Sheepstick it only provides boosts to movement speed and mana regen. The cyclone ability allows you to temporarily take one hero out of the game, but they cannot be damaged during that time making it less useful than the sheepstick. A good item if you need an extra edge.
Any DPS or Orb items are not recommended due to your poor agility.
Warlock is a great hero when the opposition has gone for a melee heavy team, especially if they are not usually blink dagger users. Upheaval will really let your team dominate fights in this situation.
Warlock is a good support pick, and especially good at supporting carries who have a hard time in the lane at the start. He synergises well with DPS heroes and heroes with big AOE nukes - adding 20%+ damage amplification to the likes of Echo Slam or Poison Nova can be deadly. Each hero bonded will take extra 20% damage from each of the other ones hurt!
Special mentions go to Venomancer who's ulti can be lethal combined with bonds, as well as Witch Doctor who synergises extremely well with your skills.
Warlock is unusual in that he provides ranged support and initiation.
Warlock should generally avoid 1v1 situations anyway, so theres not really a direct counter to him. However, he is considerably less effective in certain situations.
Characters with blink abilities (or likely dagger wearers) are much less affected by your upheaval, as its a slow rather than a stun, and they can just disappear out of it. Strong ranged carries like Outworld Destroyer are also less bothered as they can continue shooting, even if they find it difficult to escape.
Shadow Demon is worth a mention as his ultimate can insta-kill your gollum with it's purge - the same with the active purge on Diffusal Blade.
Although Warlock is reasonably sturdy, hes unlikely to have the items to turn him into a real tank, so Nukers such as Lina and Lion can do serious damage plus they have stuns that will stop upheaval being channelled.
All of the above are manageable to a point, but the real reason not to pick Warlock is if your team is desperately in need of DPS and/or Stuns.
Id keep an open mind when it comes to your skill build with Warlock you should adjust your choices to the situation rather than stick religiously to one set build.
However, heres a sample build:
1) Shadow Word
2) Fatal Bonds
3) Shadow Word
6) Rain of Chaos
7) Fatal Bonds/Upheaval
8) Fatal Bonds/Upheaval
9) Fatal Bonds/Upheaval
10) Fatal Bonds/Upheaval
11) Rain of Chaos
12) Fatal Bonds/Upheaval
13) Shadow Word/Stats
14) Shadow Word/Stats
15) Shadow Word/Stats
16) Rain of Chaos
Many of you may disagree with this build and there may often be situations where you should change it. However, Ill explain my thinking:
Start off with Shadow Word to try and get it up to level 2 as quickly as possible making it a lot more efficient to use if/when you need it. Fatal Bonds is such a useful skill, but we only want a single level in it early on as otherwise we will probably push our lane out too hard.
Upheaval comes next as ganks from either team will probably be starting around this point, and it could well be difference between life and death for either team at this point. We put 2 levels into it as otherwise its just too slow to be effective.
Rain of Chaos we want to take every time it is available the mana increase is minimal, and the Infernal much more effective.
At this point in the game, serious pushing and team fights are usually starting to develop depending on the situation and team selection, you want to max fatal bonds and Upheaval ASAP. Where youre mainly pushing, fatal bonds is obviously more useful, and can be handy for also harassing enemy heroes at the same time. Upheaval is more important if your team is lacking in slows/stuns for ganks and team fights.