Board Control Warlock: Version Two
Board Control vs Aggro
Other Good Cards
Cards That Didn't Make the Cut
How to Play the Deck
Other Major Concepts
Budget Deck Replacements
Board Control Warlock is the most consistent all-around deck. With Freeze Mage nerfed, it now has no bad matchups. Decks that try to counter it only win 55% - 60%. For that small advantage in this matchup, however, they have to accept big disadvantages in some other matchups. Board Control Warlock has a fighting chance against anything and fewer weaknesses than any other deck. It's also a deck with extremely consistent draws. I think all this makes it the best deck in Hearthstone.
The deck works by playing out early minions to get the initiative. It then uses buffing minions like Shattered Sun Cleric to help those early minions fight efficiently. Once it has the initiative, it uses Life Tap. This deck doesn't run many big minions but drawing two cards a turn puts as much, if not more, pressure on your opponent. As long as you keep the initiative, you won't take much damage; therefore, you can Life Tap all you want to fuel your attack. For more information about how this works, read my first Board Control Warlock guide.
There has been a lot of confusion about the difference between board control decks and aggro decks. A Board Control Deck focuses on getting out minions and killing the opponent's minions. It wants board control so that it can choose which minions fight each other. Controlling combat allows for the efficiency which makes up for using cheaper minions. Board control decks usually kill their opponent's minions and then slam the door on an empty board.
Board Control vs Aggro
Aggro decks are different. They are more inclined to go for the face and ignore enemy minions. They are less interested in efficiency and more interested in rushing their opponent down. Cards like Leper Gnomes, Leeroy Jenkins, Power Overwhelming, Arcane Golem, and Doomguard are definitive aggro cards. None of these cards are ideal for controlling the board and winning minion combat, but they all help kill your opponent as soon as possible.
Board Control Warlock and Aggro Warlock are different decks. If you want to play either deck properly it's crucial to understand the difference. It's common to see people make mistakes like putting Leper Gnome in a board control deck. That's bad because a board control deck should choose cards optimized for winning minion combat and getting board control: Leper Gnome's ability doesn't help with that at all. Leper Gnomes is only a good card if you're playing an aggro deck with finishers like Leeroy Jenkins and you have a game plan of racing for the win.
The Board Control Warlock deck gets confused for an aggro deck because it has the potential to kill people quickly. What this actually means is that it's a very powerful deck; you can focus on winning board control and still have a lot of the power of aggro. Additionally, board control decks have the advantage against aggro decks because they are fast enough to keep up, but are better at winning the minion battles. I consider Board Control Warlock superior to Aggro Warlock unless there is a special reason to play aggro in a meta such as Freeze Mage.
I made curi's Board Control Warlock deck around two months ago. Since then, it's been one of the most popular and influential decks in Hearthstone. I've reached nine tournament finals using the deck, which helps illustrate its power, and also helped spread it to other tournament players. I also wrote an article breaking down the deck. My Board Control Warlock article has gotten over 70,000 views. Furthermore, it helped a lot of new players who needed a really solid deck.
Due to the power and popularity of Board Control Warlock, Blizzard saw fit to nerf it. In this patch, they reduced the health on Shattered Sun Cleric and Argent Commander by one: both were popular cards in many decks. They were most popular, however, in my Board Control Warlock and Kithros' Rogue deck. Blizzard also increased the damage you take from Flame Imp by one which shows Warlock was their top target for the nerfs! These are all good cards despite the nerfs and do not need to be cut from the deck.
What hurt my Board Control Warlock more than nerfs was Freeze Mage. I spent a lot of time trying to counter the Board Control Warlock and Freeze Mage was the best counter I could come up with. When Freeze Mage got really popular, board control decks quickly dropped out of the metagame. For more information, see the Freeze Mage Deck Guide.
During the reign of the Freeze Mage, I had to adjust my Warlock deck. Like many other people, I made it more aggressive in order to get damage past Freezes using cards like Leeroy Jenkins. I was less happy with this version of Warlock and ended up playing a lot of Mage.
Now, Freeze Mage has been nerfed; rather, all Mages have been nerfed. Blizzard and Cone of Cold were two of the scariest spells for Warlock to face from any Mage deck. After being nerfed, they are at a weaker power level than you want for a constructed playable card. They can still hurt you but on average are far less of a problem. After the Freeze Mage nerf, I figured Board Control Warlock would be good again. A others seemed to agree Warlock once again became the most popular ladder class.
The problem was, I didn't want to play the same old deck. I figured that Mage was nerfed so much I could rebuild the deck without worrying about Mage. I made a new version of the deck and it's working better than ever. A lot of people have asked me for the decklist and I've decided to share it!
- I reached Legend after the Freeze Mage nerf with this deck. I had a 10-0 win streak with it at the top of the NA ladder, reaching #6 on December 20th.
- Both monk and I have peaked at #2 NA Legend with this deck. Many other friends who I've shared this deck with have reached Legend.
- Trump showcased the deck in KoTH #8.
- 1st Place 2p Daily #23 Team Tournament, played by curi, See Tournament Video here
- 1st Place 2p Daily #24 Team Tournament, played by curi, monk, and Strifecro
If you haven't read my original Board Control Warlock article, do so before you continue. The plan is to explain the rationale behind the changes and then we'll look at each individual card change.
The moment you have all been waiting for! Left is the original deck: right is what it has become.
My goal was to make the deck more consistent and more minion based. No longer having to worry about Blizzard, Cone of Cold, and Fireblast, makes smaller minions more viable. With less worry about racing Mages before they Pyroblast me, burst damage in the form of spells becomes less valuable. The changes aren't all inspired by ignoring Mages or other metagame factors. I wanted to make the deck laser focused on board control: I think it's even better designed now.
And here are the curves in comparison.
+2 Young Priestess
Young Priestess puts the deck up to ten one mana minions; therefore, one third of the deck costs one and it's amazing. Her downside is that she's fragile; however, the deck has many ways to deal with that. The Priestess can be protected in up to nine ways. You can increase its health with Shattered Sun Cleric, Defender of Argus, or Blood Imp. You can use Voidwalker's Taunt to protect it from Shapeshift and Dagger Mastery. The Priestesses can also buff each other. Young Priestess provides more value the longer she lives -- and even if she doesn't -- she's good at trading for two mana minions or otherwise helping you get the initiative.
While Young Priestess can be fragile, she can also make your army less fragile. Her health buffs can help get your minions through board clears: Consecrate being the most popular. Even if she dies to Consecrate, another minion may live on in her place.
+2 Harvest Golem
Harvest Golem was always a pretty solid card. Thanks to its second life, it helps increase the odds that one of your minions survives to be buffed and attack the next turn. It also has a decent chance of killing two enemy cards by itself. Additionally, both the first and second life benefit from Blood Imp, so it ends up with a functional two additional health total for your opponent to worry about.
Since the deck's first iteration, Harvest Golem has gotten even better for three reasons: firstly, Fireblast will kill the Damaged Golem less frequently; secondly, Harvest Golem can now kill Shattered Sun Cleric; and finally, Harvest Golem can now kill Argent Commander.
The two attack is a bit low for an aggro deck because it doesn't pressure the opponent's life total enough: this isn't a problem in a board control deck. Minions with low attack make a deck more vulnerable to board clear spells because more minions are needed to kill your opponent; however, thanks to the Mage nerfs this is less of a concern than before. (Note that Voidwalker, Novice Engineer and Argent Squire are in a similar situation. They are good board control cards, but don't pressure as well as aggro would want.)
+1 King Mukla
If you have board control, the Bananas won't do much for your opponent. Mukla is a really powerful card for capitalizing on initiative once you get it. He's also usually amazing on turn two or three.
Watch out because Mukla does have some weaknesses: Bananas are powerful on Wild Pyromancer or Mana Wyrm; and they work great with Rogue combos, Gadgetzan Auctioneer, or Soulfire. Perhaps the worst thing that can happen when you play Mukla in the late game is an Argent Commander with a Banana killing Mukla before you attack.
Don't be afraid to play Mukla against an opponent's three attack minion. You should be fine if they have a 3/2, play two bananas, and kill Mukla. They spent four mana, you spent three mana, and you each used up one card. If Mukla trades evenly, or gets you ahead in mana, you should be happy. He has potential to win games, but if he just trades evenly that's nothing to worry about. Trading evenly can be good for you because you can replace cards easily with Life Tap.
+1 Defender of Argus
If you're going to focus on board control, you need to take advantage of it. This deck has a better chances than any other of getting two guys out that stay alive: Defender is obviously really strong with two targets.
+1 Mortal Coil
This is a metagame choice. A lot of good targets are popular, and running two Mortal Coil has been doing very well for me lately. You don't even have to worry much about them being useless against a Freeze Mage anymore. If the metgame changes -- and you find Mortal Coil isn't having enough targets -- feel free to reduce it back to only one Coil.
+1 The Black Knight
This is another metagame choice. Taunt is popular and Black Knight is really powerful if he has a target; furthermore, big taunts like Ancient of War and Earth Elemental are some of the more best cards against us. Against other board control or aggro decks, Black Knight can kill something that got a Defender of Argus buff, or kill a Voidwalker/Stoneclaw Totem. Even without a target, Black Knight is inefficient (two mana overpriced) but still not a total disaster.
-1 Lord Jaraxxus
Nine mana is a lot and it's hard to play Jaraxxus if you aren't already ahead. If you're behind, you usually die 1-2 turns after playing Jaraxxus and without being able to attack with an Infernal. I removed him from the deck for consistency and focus on the early game board control. Plus, I'm now less worried about getting Pyroblasted and needing to heal up.
Shadowflame is an inefficient card which kills your own minion. It's also situational and only works well if you have a high attack minion and your opponent has several minions. It doesn't help you get board control, it only helps if you lose board control. I cut this card to focus more on getting board control in the first place. Plus the interaction with the Infernals from Lord Jaraxxus is now gone.
-1 Azure Drake
Azure Drake is OK, but it's a little bit slow and quite greedy. You don't need Spell Damage all that much, and you draw cards from Life Tap. Azure makes your early game less consistent and isn't that effective in comebacks.
-1 Bloodmage Thalnos
Thalnos is situational. Sometimes he's helpful, sometimes he's not. The downside isn't very big when the Spell Damage isn't useful, but it is some downside. Removing him helps make the deck even more consistent.
Demonfire is overrated because it's strong on turn two following a Voidwalker or Flame Imp on turn one. Using it on a Flame Imp is risky, but it does win games sometimes. With a Voidwalker, you can get a big guy out quickly who is hard to kill and it seems really strong. It is strong, but look at it this way: your 3/5 for two cards and three mana can easily be killed by two 3/2 minions for two cards and four mana. If that happens, you gained one mana. That's good but it's not as amazing as people thing.
Demonfire is a situational card without a big enough upside: sometimes you don't have a demon that you want to buff; other times, your opponent doesn't have a minion with two health; or worse yet, Demonfire sits in your hand when you only wish you had some minions to play instead. The best case scenario with Voidwalker usually doesn't get you more than a one mana lead. Killing an enemy minion with Demonfire usually trades evenly or worse.
In Hearthstone, removal spells are a lot less needed than in Magic: The Gathering because in Hearthstone all your minions can work as removal spells. Need to kill his two health minion? You can just attack it with one of your minions, no problem. So I now prefer to play with more minions instead of Demonfire.
-1 Power Overwhelming
Power Overwhelming is too much of an aggro card and can sit in your hand uselessly during struggles for board control. It did have some nice upsides: you could kill a big taunt with it; you could combo it with Shadowflame/Sylvanas Windrunner; you could use it on an expendable Novice Engineer to kill something. Overall, however, I don't think it's worth it. I think it's really important to minimize situational cards and have your whole deck be useful and consistent all the time. Situational cards can be worth it if they have a huge upside; but if the upside isn't huge, the downside of being situational should keep it out of your deck.
-1 Novice Engineer
Novice Engineer is less useful without Power Overwhelming since you have less need for an expendable minion. It's a little bit slow and not doesn't trade well: drawing two of them together could slow you down too much. Dropping to one Novice helps make the deck more consistent by preventing this potential situation. It's still a useful card as a buff target or a way to deal one damage to something. Drawing one won't slow you down too much and late game its a free Life Tap.
Here are some other cards to consider in approximate order of how promising they are. They're also all very good replacements should you not have all the cards required to build this deck:
Other Good Cards
Novice Engineer, Loot Hoarder, Bloodmage Thalnos
The cantrip minions are solid cards but a little slow. Loot Hoarder increases your vulnerability to hero powers that deal one damage and Bloodmage Thalnos is a little too situational.
Abusive Sergeant, Elven Archer
These additional one drops both have nice abilities but they increase your vulnerability to hero powers that deal one damage. They also play into board clears.
Faerie Dragon, Acidic Swamp Ooze
The deck is a low on two mana minions. 3/2 minions have larger short term benefit than the cantrip minions but are worse top decks later. Faerie Dragon and the Ooze both have situational abilities that are useful sometimes but frequently ineffective.
Silence has some merit: it can remove taunt, help with Sylvanas, remove Freeze (much less useful after the Freeze nerfs), and remove buffs like from Shattered Sun Cleric. Silence is good against cards like Nat Pagle, Lightspawn, and Doomsayer. It's also OK against some cards like Twilight Drake, Harvest Golem and anything with Divine Shield. If you want to run silence, I like Spellbreaker more than Ironbeak Owl because the 2/1 can be killed too easily.
Emperor Cobra, Scarlet Crusader, Razorfen Hunter
This deck can't support many three mana minions. Scarlet Crusader is almost as good as Harvest Golem. I think it has a bigger upside than Harvest Golem, but also a bigger downside, and I value consistency higher: Harvest Golem also triggers Blood Imp and Knife Juggler twice. Scarlet Crusader can at times be fragile, but it is a good card that we probably shouldn't forget about.
Emperor Cobra is a potential solution to big minions. I prefer it to Siphon Soul or Shadowbolt, but it's still situational. I don't use it right now but that isn't to say I won't in the future. Note that it actually has to damage things to kill them making it weaker against Divine Shield.
Razorfen Hunter benefits twice from Blood Imp and Knife Juggler and helps you get board control pretty well; however, a 1/1 can be fragile.
Azure Drake, Silver Hand Knight
Azure Drake is too slow and the Spell Damage is unnecessary. Azure Drake reduces early game consistency and makes bad hands more likely. On the plus side, it is a better turn five play than Life Tap plus Harvest Golem. The card draw on Azure Drake is a better deal than the card draw from Life Tap despite being packaged in a five mana bundle. While I'm not using Azure Drake currently, I wouldn't forget about it completely.
Silver Hand Knight is another pretty big card: it too benefits twice from Blood Imp and Knife Juggler. It helps you get a big army quickly. It is, however, five mana (that's a lot!) and the 2/2 might die to board clears. Compared to Azure Drake, you're giving up drawing a card and Spell Damage for the 2/2 minion. A 2/2 is play can be better than a card in your hand and certainly helps more in the short term, but it can also be less powerful if your hand is empty.
Cards That Didn't Make the Cut
Unlike the previous section, adding the following cards in this section will usually change the nature, feel, and purpose of the deck. For example, many of the cards listed here are cards that typically belong in Aggro Warlock decks.
Power Overwhelming, Demonfire
As discussed earlier, Power Overwhelming is too much of an aggro card. Demonfire is a situational card without insufficient upside.
Leeroy Jenkins, Arcane Golem, Doomguard
I think Leeroy Jenkins is the most promising aggro card for the deck, but I still don't really want an aggro card. It hits the hardest for a single card and you can use it to kill big minions if you need to. Finishing games faster can avoid some risks sometimes. However, if you use Leeroy as removal then the two whelps are a nuissance. What I especially don't like is that he's situational: sometimes he sits in your hand for a while. Situational cards make the deck less consistent and also make it hard to get an empty hand Soulfire.
Doomguard and Arcane Golem are a lot weaker than Leeroy Jenkins. Their downsides are a big problem and they deal less damage. If Leeroy isn't in your deck, you definitely shouldn't use Doomguard or Arcane Golem.
Siphon Soul, Shadow Bolt
Overpriced removal. No thanks. Emperor Cobra is probably a better option compared to these. Using minions for your removal can get you more Knife Juggler activations and they have a better worst case scenario.
I'd rather focus on getting ahead than worry about a comeback. I think Hellfire makes more sense in an aggro Warlock which is at more risk of losing board control, and which can also use it as reach.
This card only makes sense if you're going straight for the throat: the Death Rattle does nothing for board control. Some would argue it's a solid card everyone should craft; however, it only works in an aggro all-in rush only card. That helped vs Mages but I think board control is in a better place now.
Nat Pagle eats up early mana when you should be trying to gain the initiative and you've got Life Tap anyway for drawing plenty of cards later. I think he's more useful in risky aggro decks that are trying hard to draw a big damage hand with Leeroy Jenkins, Power Overwhelming, and/or Soulfire.
Giving your opponent a 5/5 is a huge risk. Trying to get a 5/5 from one of your own minions is a huge risk (and if it works, it cannot attack until the next turn). The Board Control Warlock is pretty good at having minions out that it can kill threats with: use them instead. It's better to focus on the main strategy and use the deck's strengths to deal with problems. Tinkmaster is a situational card that will often sit in your hand uselessly, block empty hand Soulfires, and make the deck less consistent.
I explained the deck in the original article but let's recap a bit and get an updated look at the essentials.
How to Play the Deck
Most minions in the game do not have Charge. You play them and then you wait and they might get to attack on your next turn. Blizzard seems to consider non-Charge minions fighting each other to be the standard type of gameplay they want to encourage -- and decks which work in other ways have been nerfed (Miracle Rogue and Freeze Mage) -- or removed radically changed (Unleash the Hounds).
You have Board Control when you play minions and then get to attack and choose pick the fights. You typically keep board control by clearing out your opponent's minions each turn while also playing new ones. In this situation, you have a lot of control over the game which gives you a significant advantage.
If you do not have board control, your minions usually die without attacking. Even if you do have board control, minions usually don't live very long. minions die to kill enemy minions or due to removal spells. This makes Battlecries and Death Rattles good because even if a minion dies, they haven't been completely impactless. Battlecries are better than Death Rattles because you benefit sooner rather than later, and you have better control over when it happens: Death Rattles are also vulnerable to Silence.
Suppose I played a Shattered Sun Cleric and buff my Argent Squire. Then my opponent kills the Sun Cleric with Backstab. We've each lost one card, but the +1/1 Battlecry bonus is still in play. It's common that using single target minion kill spells gets you a disadvantage because so many commonly used minions already got to do their Battlecry before they were killed. This is another reason why the Board Control Warlock deck uses a lot of minions and not very many removal spells.
Battlecries are powerful: so is claiming Board Control. These naturally fit together. Some of the best Battlecries work better when you have board control. In particular, Shattered Sun Cleric, Dark Iron Dwarf, and Defender of Argus work best with board control. If you already have minions out, you can play them earlier in the game -- instead of needing mana to play a target for them earlier in the same turn -- and those minions can attack with the buff immediately: essentially the +1/+1 from a Sun Cleric has Charge if you play it on a minion that you cast the previous turn. When you control which minions get buffed and fight, you can win minion combat very efficiently.
Charge minions are mostly on the weak side, and single target removal spells are mostly on the weak side because they don't remove the Battlecry or Deathrattle. Hearthstone therefore revolves around minions without Charge; and to take advantage of that, it's important to get board control to make up for not having Charge.
Some board clears spells are pretty strong -- like Consecrate, Avenging Wrath, Lightning Storm and Hellfire -- and you have to watch out for those. Board clears are the main thing which circumvents the normal fighting between non-Charge minions. However, because the deck has eight cards which can increase the health on minions, it's often possible to have multiple minions live through board clears spells. Know what board clears your opponent might play and make sure to set up your minions with the right amount of health when possible.
You should usually kill your opponent's minion. If you ignore a 1/1 he might use Abusive Sergeant on it and kill your 5/3. They may also have the mana to play Defender of Argus and one other minion, so the 1/1 gets a buff that would otherwise have been wasted. Suppose you have a 2/2 and don't kill their 1/1, then your opponent might use a two damage spell on your minion like Arcane Shot; if you'd killed his 1/1, one of the damage from Arcane Shot would have been wasted and you'd be better off. Another example is if you have three 3/2 minions and your opponent has two 3/2 minions, you should still trade. By trading off his minions, you reduce your vulnerability to board clears spells.
The later the game gets, the more you can consider attacking your opponent directly. When he's nearly dead, consider finishing him off. Note that if attack him and his minions then trade with yours, you can get a significant life lead, and sometimes that will lead to a kill. To get this damage on his hero you're sacrificing some efficiency because you let him select the minion trades. On the other hand, early in the game it's almost always best to focus on board control and guaranteeing efficient minion trades. Even late in the game, clearing your opponent's minions is frequently the correct play.
It can be tempting to attack your opponent when you have a taunt minion -- or there's a limited amount of possible minion trades -- and it doesn't appear make much difference. For example, if you both have a 3/2 then you might want to hit your opponent because he won't get any advantage from being the one to make the trade. But be careful! What if he has Power Word: Shield? Then his minion could kill yours and live. When in doubt you should always trade minions to avoid getting screwed over by your opponent's tricks. Only if you know exactly what cards he might have in his deck, and you think through whether any of them would cause you problems, then you can get away with a few extra points of damage on your opponent.
Damage on the opposing hero isn't crucial. Many games would have the same outcome even if the losing player had an additional 20 health. Don't take big risks for a little damage early, but you can consider taking small risks for some damage that looks more likely to matter.
Other Major Concepts
- Board control
Board control is defined as you having minions out while your opponent doesn't so you can keep killing his new minions each turn. This is a good situation because your minions get to attack but his don't. That means you can decide which minions fight each other in a way that's efficient for you, and it means you can deal damage to his hero.
- Non-charge minions and Board Control
Most minions in the game do not have Charge. To be very effective, therefore, they have to live at least one turn to get the chance to attack. This requires board control. Blizzard considers minion combat -- without Charge minions -- the core gameplay; therefore, Board Control is one of the most important factors in Hearthstone.
- Battlecries vs single target removal
Battlecries are another major part of Hearthstone. They are important because they allow a minion to do something even if it never gets to attack. Some Battlecries are useful even without board control, but attacking is still a bonus.
Since Battlecries (and Death Rattles) are common, single target minion kill spells are not always effective. If I spend a card to kill your minion card, that might look like a fair one-for-one trade, but if your minion had a Battlecry (or Death Rattle) then you actually got the better deal.
- Trading up
If you have the initiative, and decide which minions fight each other, you can trade lower cost minions for higher ones. Trading your turn two Knife Juggler for his turn three Earthen Ring Farseer often enough can put you ahead. Trading in this way helps make up for having a low mana curve in your deck while also increasing your initiative by being more mana-efficient than your opponent.
- Trading efficiently with Buffers
Trading up works even better with cards like Dark Iron Dwarf. Using a Dwarf, you can trade Flame Imp for Fire Elemental or Sen'jin Shieldmasta. Buff minions also often allow you to kill an enemy minion while yours lives. For example, your 2/3 Harvest Golem would die against a 3/2, but with a +1/1 from Shattered Sun Cleric it can kill that 3/2 and live.
- Trading inefficiently but still being ahead
The Board Control Warlock is good at getting an early advantage, and it's good at using that initiative to draw extra cards with Life Tap. The result is that you can often make some inefficient trades and still be ahead. If the game is going well, but your opponent drops a minion like Sunwalker or Ancient of War, you might have to use up three cards dealing with it. Do not despair. Sure he got a good deal this turn, but you might still be ahead in the game overall. To beat you, control decks will typically need to multiple efficient trades in a row.
You can also make inefficient trades against aggressive decks. They will run out of cards long before you do so just focus on not dying. If you have to trade your Knife Juggler for their Leper Gnome, you'll still be able to win in the long term, as long as they don't run you over.
- Playing around board clears by Life Tapping or leaving cards unplayed
Sometimes you have enough minions out and there isn't much your opponent can do about it: except slaughter them all with a single board clear. There often comes a point where your opponent won't get board control back just by playing more minions; when this occurs, you should usually use Life Tap every turn and only play minions with your extra mana. This prevents you from over extending or running out of cards. In extreme cases where board clears are the only thing you're still worried about, you can even pass your turn while saving minions in your hand.
- Playing around board clears by trading off minions
If you trade off your early small minions, preferably by trading up efficiently, you become a lot less vulnerable to board clears. You can also reduce your risk by sacrificing some of your minions to keep others at high health. For example, you might considering trading your 3/2 for a 3/3 rather than killing it with your 4/4. Normally it's better to keep more minions alive; but if you trade off your weaker minion, you'll be better off against a two damage board clears.
To do this well, you have to have a good feel for the game. Try to understand that board clears are the main way you might lose and you can afford to be inefficient against other things to be more efficient against board clears . The goal is to play in a way that is good enough to win if he doesn't have board clears, and also works better if he does.
- Turn 2 Life Tap vs one 1 mana minion
A reasonably common scenario is to have a one mana play on turn two. You can either leave one mana unused or you can Life Tap. How do you decide? First, look at your hand. Do you already have all the cards you'll need for the next several turns? If so, you should probably play your minion. Don't Life Tap in hopes of benefiting four turns later when you can get an immediate benefit: the early turns are more important to getting Board Control.
Consider your opponent's deck. Is it a fast deck that can fight you for the early initiative? If so, play your minion. Is it a slow deck that tries to win through card advantage? If so, consider whether your hand will be able to get a quick win; if you can, go ahead and play your minion; but if you can't, then drawing a card will help your long term chances more.
Consider what's already been played. If you have a Flame Imp out against nothing, don't feel too bad about using Life Tap. If, on the other hand, you have a 3/2 Flame Imp against a 2/1, then you'll want to play your Blood Imp or Voidwalker to more contest the board.
Consider the benefits of having the extra minion out. If it's a Blood Imp, will it protect your other early minions against the cards your opponent is likely to play? If it's a Young Priestess, will have a good chance to activate its ability several times? If it's a Voidwalker or Argent Squire, will it do much or just attack for one damage a couple times? Do you have a Shattered Sun Cleric that will need a target next turn?
- When to go for the kill
It's rarely correct to attack your opponent in the early game when you can get an advantageous fight, even if your minion has Taunt. Leaving your opponent's minions alive opens up a risk to buffs and a swing in momentum: what if they have Defender of Argus or Abusive Sergeant? Before you attack the enemy hero, consider every card he might have to make combat go in his favor next turn and make sure none of them will hurt you.
Later in the game, it's more worth taking a risk for damage. You can consider factors like whether you may be able to end the game soon by dealing damage, whether you're behind and need to take a risk, and whether you'll still be doing fine if he has combat trick. Still watch out for board clears! Leaving your opponent's minions alone is something you'll usually regret if he sweeps yours.
- Life Tapping vs playing more minions
It's important to learn how much you need to Life Tap to avoid running out of cards. It varies by matchup. You want to make sure not to run out of cads before the game ends, but there's no point in having more cards than that.
- Who's the beatdown?
In each game, try to figure out if your opponent is playing a more or less greedy deck than you are. If his deck is more greedy, you'll want to play aggressively, take a few risks, and get in some damage: his greedy card choices will give him the advantage in the long run. On the other hand, if your opponent has a less greedy deck than you, then you should understand that he will be the aggressor and you just have to defend.
- Key Turns
If the only way your opponent can win is by casting Flamestrike next turn, and he'll only have seven mana, then you don't have to worry about exposing a one health minion to Fireblast: whether by attacking a 3/3 with your 4/4, playing a Young Priestess, or attacking with a Blood Imp and losing stealth. If he Fireblasts that minion and can't cast Flamestrike, your other minions will win the game for you.
There are many situations where your opponent needs to do a certain kind of thing or else he's in big trouble: don't have to worry about other plays. Board clears are a common example but not the only one. Suppose your Druid opponent will have five mana next turn and you are pressuring him well with minions. Do you have to worry about Shapeshift? Not very much. He needs a strong play like Druid or the Claw, Sylvanas, Starfall, or Innervate with Ancient of Lore. If he plays Shapeshift and Harvest Golem, your momentum will continue, your advantage will grow, and his life will get lower: it won't really matter that his Shapeshift killed one of your minions.
In general, using a hero power can be awkward on the key turns three to six. People frequently need to play important cards during those turns and will skip their hero power even when it would have been useful. This is an angle you can exploit. When you recognize that your opponent can't hero power next turn -- he needs to play something bigger or you'll be ahead anyway -- you don't have to play around his hero power.
- Spending all your mana
Usually the plays which spend all of your mana are best. You should have a very good reason to waste mana. Considering the power of Life Tap, one mana is kinda like half a card! It's important to make efficient plays in terms of minion combat, putting out minions in the ideal order, killing your opponent's minions before they get to attack, and so on: but it's also important to make mana-efficient plays. Look for ways to do both. If you can't, consider carefully.
Budget Deck Replacements
The deck has three legendaries and no epics. You can play it without any Legendaries and do well. You would be disadvantaged, but it will not ruin the deck. The Legendaries are powerful cards but they aren't essential to the deck's playstyle. Let's consider them in order of importance:
#1 Sylvanas Windrunner
Sylvanas is the best neutral card in the game. She should be run in almost every deck and be your first legendary craft. If you don't have her, there are no other cards which can take fill her role. She can be replaced by a card like Novice Engineer (see the Other Good Cards section) -- or perhaps a Silver Hand Knight to keep the same mana curve -- but nothing can do her job. You could also try Emperor Cobra since it can kill big things and Sylvanas also helps deal with big things sometimes.
#2 The Black Knight
The Black Knight is a metagame choice. The more people use Taunt, the better he is so right now he's great. If you don't have him, you could consider Abusive Sergeant to help you kill big taunters or Spellbreaker to remove their Taunt. Note that Silence turns a 5/10 Ancient of War into a 5/5 but does not lower the stats of Druid of the Claw. Emperor Cobra is another way to approach big Taunts. Keep in mind, however, that The Black Knight can also be used on small taunts and provides good value there too; there is no exact replacement, but any good card will work OK.
#3 King Mukla
Mukla is a powerful card when things are going well, and he's usually pretty good in close games. Even if you're losing he doesn't usually cause a disaster. While a bit risky, Mukla can really help you benefit from board control once you've got it. No other card works the same way. A possible replacement would be Azure Drake because it's usually better when you're already ahead. It might, however, be better to just put in any of the good cards mentioned earlier.