Every once in a while, not as often as I wish, I meet some new player in game that asks me how to tank. I like the game very much and I believe I can transmit some of my enthusiasm to new players with the proper answer to this question, but no matter how much I try, there are several aspects to be covered and a simple straight answer is not enough.
I know there are many articles on the internet to explain tanking, but I thought I would write an introduction on the subject, without going into all the details, for people that are curious but are not yet familiar with the subject. I will try to keep the discussion generic and not get into abiltiies or details specific to a certain class, but that is not always possible so I may leave out aspects important to some classes like druids. In order to do the job right, you still have to know your class and I suggest you also consult a guide that is specific to your class, once you understand the basics.
There are four classes that can tank in Wrath of the Lich King expansion: warriors, paladins, death knights and druids. Blizzard has gone through a continuous process of balancing all classes so they are equally good, including for tanking. But the balancing process takes time and experience to get right, and in a way it is never complete (it is a continuous process), so the popular belief that warriors are particularly suited for tanking (and priests particularly suited for healing) still persists.
In a general view there is a technical aspect and a social aspect related to tanking. We will start with the technical aspect.
The creatures you encounter in the game are generally called mobs. The term actually means "movable obstruction" and was first used be game developers (programmers) for both friendly and aggressive creatures. Aggressive creatures are technically called creeps, but players are normally using the generic term mobs for them, and use the term NPCs (non-player characters) to refer to friendly non-player creatures.
Damaging a mob or harming it in any way generates aggression from the mob towards you. Of course a mob will aggro you on sight as soon as it can see you, even if you are not the one to hit first, but the point here is: as you hit the mob more, the mob hates you more. Thus there is a measure of how much aggression (or enmity) a mob has built towards you at any one time during fight, which is called threat. Aggro means the mob is targeting you.
The plain damage you deal (with your weapon) generates threat, which in this case is by convention considered equal to the damage. But your class abilities can generate more threat than damage, or even more damage the threat. Threat adds up during fight, the same way you can sum the damage dealt. The tooltip (description) for every ability normally includes the amount of damage (at least up to version 3.3.5a, that is), but not the threat generated by the ability. Some ability tooltips, like Heroic Strike (warrior) for example, will say: "causes a high amount of threat". The paladin ability Righteous Fury says even more: "Increases the threat generated by your Holy spells by 80%". If you install a proper add-on you can actually see the amount of threat for each of your abilities, but I do not recommend add-ons yet.
What this all means is you can generate more threat than damage for a mob if you use the proper abilities, or if you want you can generate more damage than threat. This is not important when you are playing alone (leveling solo) and the mob or mobs will simply aggro you, but it is important when you are in a group. The mobs you fight will attack the player that generates more threat against them, even if damage from that player is not high. There are mobs that do not follow this simple rule at all times (they "switch aggro"), but they are special encounters and we will not disscuss them here.
Some people have a simplified view of what a tank is: at any moment during fight, the player that is taking damage from the mobs is the tank. While this is correct, it is not neccesarily sufficient. You have to add that a tank also assumes this role, usually for the entire run, and they specialise for it. Note here that tanking is a form of protecting your group: if you (the tank) take all the damage from the mobs, other players are not taking damge, so they are safe. The job of a tank now becomes:
- to take aggro from the mobs at all times (ensure mobs are attacking the tank)
- to be able to take the damage and stand up in front of the mobs
3. Defenses (stamina/HP, armour, avoidance)
You may rightfully wonder how can just one player in the group take all the damage from all the mobs. Well, in real life this may not be realistic, but here we are in the World of Warcraft. The game will correctly follow certain formulas to compute how strong you are and how much damage you get. These are called game mechanics, and you should know a few things about them.
In order to take and withstand the damge from all mobs, you (the tank) are the main target and the main concern of the healer in your group, which is the player that heals you during (and after) the fight when you take damage, using their healing abilities. As a tank you may or may not have abilities to heal, but even if you do, you are concerned with other priorities (generating threat and keeping aggro) that ordinarily do not allow you to use these abilities. So you need a healer in order for you to tank.
Even with the group healer continuously healing you during fight, you still have to observe several statistics for your in-game character in order to absorb all the damage, and these are:
- your total hit points, or health. These are proportional to your stamina, and you need as much stamina/health as you can get. A large amount of hit points (HP) allows you to stay alive a few more seconds when all the mobs are hitting, and this allows the healer a few more seconds to cast the heals and keep you alive during fight.
- your total armour. This should be obvious: if you want to take a lot of damage, you need as much armour as you can get. A point to note here is if your class can equip a shield (paladins, warriors), than you need one. Some tanking classes can not equip shields (druids, death knights), but they have other game mechanics to compansate for that. When you use a shield you can no longer use a two-handed (2H) weapon, and must now use a one-handed (1H) weapon, with lower damage. That is ok, because your role as a tank is to take damage, not to deal damage.
- your total avoidance. Your in-game character does not have to take (absorb) every hit that lands. What you can also do instead is:
- parry the attack with your weapon. A parry is followed by an aditional auto-attack, which is considered an advantage.
- block the attack with your shield. This only happens if your class can equip a shield (paladins, warriors). Death Knights for example equip weapons instead of shields and as a result they use parry instead of block. Blocking an attack prevents only part of the damage for that attack from reaching you, which is known as your block value. If you get hit harder than your block value (and you happen to block that hit), than you will absorbe (you will "feel") the difference between the hit value and your block value. Your block value increases with your strength, and it may also be a bonus from some items you can equip.
- dodge the attack. This avoids the attack entirely, and does not rely on your weapon or shield.
- the mob misses on its attack on you. There is nothing you do for that, and this is not a parry, block or a dodge. The mobs simply does not hit you right and the attack misses.
- spell damage reduction. Physical damge from melee (hand-to-hand) combat is not the only damage you can take as a tank. You will also encounter casters. They have this property that their spels completely ignore your strong armour and high avoidance, and bite directly from your hit points. However, there is little you can do about this. Whatever spell resistance you may get in the game will be insufficient for protecting you from spellcasters, and usually you have to deal with them another way.
There is more to be said about your avoidance. On your attack, on every weapon swing you have a chance, ususally between 95% and 100%, to hit your target with the weapon, but you also have a small chance to miss, and a small chance to critically hit. A critical hit means you hit the target for double the normal amount of damage.
With proper gear you can improve your chance to miss and chance to critically hit, to your advantage, but by default against an equal level opponent, your chance to miss is equal with your chance to critically hit (5% for each) so that on an average your hits will output the expected amount of damage as if you always hit straight.
The same discussion holds true for every mob that hits you. The mob has a chance to hit, a chance to miss and a chance to crit. If a mob is higher level than you, it has a higher chance to critically strike you. Another form of avoidance is avoiding critical strikes from the mobs, which is of particular importance at high levels in raids.
Just as you can dodge attacks from the mobs, a mob can dodge attacks from you or from your group. Mobs do not usually have shields, so they do not block. They do use weapons sometimes, so they can parry, but I could not tell you more about that.
So as a tank you want to improve your own avoidance, and to overcome avoidance of the mobs you are fighting. The later depends on two other statistics (stats) for your in-game character:
- to reduce chance to miss on your attacks, you want to increase your hit or hit rating.
- to reduce change to be dodged/parried/blocked, you want to increase your expertise