There seems to be a lot of confusion among neophyte feral Druid tanks about the amount of defense rating that they need to acquire on their gear in order to tank effectively. I have received numerous emails on the subject, as well as repeatedly noticed player specs and gear that are suboptimal due to misconceptions surrounding this topic.


Quick and dirty answer
If you don't care about the rationale behind the answer to the question posed by this article, then here is your simple answer:

A properly specced feral Druid tank needs ZERO defense rating on their gear.

If you care to learn why this is, and why the subject can become so muddled, then read on.

What does defense rating really do?
Like all stats in the combat rating system, defense rating converts into defense skill. Defense skill's effects are summed up nicely on WoWWiki:

Each point of +Defense skill adds 0.04% to the chance to be Missed, to Block, to Dodge and to Parry for players. This means +25 Defense will grant you an extra 1% Miss, Parry, Dodge, and Block. The formula is constant across all classes. It further decreases the chance of receiving critical hits from any level attacker by 0.04% per point that the target's Defense skill exceeds the attacker's Weapon Skill.

In terms of tanking, all of these stats are desirable, however the crucial mechanic is the reduction to a mob's critical hit chance.

Why is being crit immune a Big Deal?
Back in 2007 I explained the importance of not being critically hit as follows:

While you may have amazing statistics and the ability to take a massive pounding, even allowing enemies a sliver of chance to critically hit you can have serious consequences when you are raiding. If nothing else, Murphy's Law states that you are going to take a big crit at exactly the wrong time if you allow the possibility to remain open - so why take the risk?

Besides your own survival, part of your job as a tank is to make things as easy as possible on your healers.

In fact, being uncrittable is so important that most raids refuse to allow a tank who is not crit immune to run with them: uncrittability is usually the entry bar that is set.

So how do I get crit immune?
Raid bosses possess a 5.6% chance to land a critical strike with every attack, and so to completely eliminate the possibility of absorbing a critical hit you need to reduce that percentage to zero.

Thankfully, as a feral Druid obtaining crit immunity couldn't be easier - all you have to do is invest three talent points in Survival of the Fittest and you will be instantly granted a 6% reduction to your chance of being critically hit.

That's all you need to do to become crit immune - nothing more.

Specced like this, you can tank naked and still never suffer a critical hit - you may die in a hurry.... but that will be due to a lack of health and armor, not because you ate a critical strike.

Okay, so why the confusion?
If it is so easy for a feral Druid to get crit immune, then why is there so much misinformation and confusion out there? The answer is two-pronged: history and other tanking classes' mechanics serve to muddy the water on what ought to be a no-brainer.

Prior to Wrath of the Lich King, Survival of the Fittest only reduced a Druid's chance to be critically hit by 3%, so bear tanks were left scrambling to mix and match gear to make up the remaining 2.6% deficiency however they could. This often led to some crazy gear juggling since leather with +defense was scarce. The result is that players who are not completely up to date on bear tanking remember the games that we had to play to stay crit immune in the last expansion, and just assume that the same is true today.

Further confusing the subject is that fact that all of the plate-wearing tanks need to stack defense rating to become crit immune - they have no "I win" talent to automatically acquire their immunity. This can mistakenly lead tanks that are not intimately familiar with feral mechanics to believe that bears also need to stack defense rating.

So should I just throw away all my defense gear?
Well no - despite not being a crucial stat for feral tanks, defense rating still serves some purpose as an avoidance stat. There is nothing wrong with acquiring the extra miss and dodge chance that defense rating rating bestows, although other stats are generally more desirable. Don't avoid gear with defense rating - just don't go out of your way to jump all over it.