Chance to Crit vs Multiple Mobs

Assuming we never miss, and are never blocked, parried, or dodged, how often will we be able to proc Savage Defense while using Swipe versus multiple mobs?

To find our chance to crit on a Swipe during a trash tanking scenario versus numerous mobs, we need to understand how the combined probability of our base crit chance stacks up.

Put another way, a 33% chance to critical strike on an attack doesn't yield a 99% chance to critical strike when attacking 3 mobs simultaneously. The actual number is closer to 69.92%, because of how combined probability works.

The formula for calculating crit chance versus multiple mobs is actually the following recurrence relation:



Where n = number of mobs, and c = chance to crit versus one mob.

This formula yields the following values for a range of base critical strike chance:



See also: spreadsheet for critical strike chance versus multiple mobs.

Bear Market for Druids in 3.1 PTR

I've been coming to terms with the changes coming up for druid tanks in 3.1. If the changes in the 3.1 PTR go live, it will be the most significant change for Druid tanking since WotLK came out.

The four primary changes to bear tanking can be summarized as follows:

1. Survival of the Fittest armor gain cut in half.
   
2. Heart of the Wild stamina gain cut in half.
   
3. Primal Gore talent gives Lacerate ticks a chance to crit.
4. Melee crits reduce next physical attack by 25% of your AP.
   

If these changes go live, it will seriously shake up feral tanking. Blizzard seems determined to blur or remove the distinction between bears and cats. Strength will now partially substitute for stamina in contributing to our Effective Health, as our hit pools are reduced and attack power grows in importance. Critical strikes become more important than ever in this new paradigm.

Ostensibly these changes are to help our healers from having to fill our oversized health pools in light of the upcoming nerfs to mana regeneration, but my guess is that reduction in mana waste from overhealing made up much of the difference.

Some folks have helpfully suggested to me that it'll be a great change because feral druids won't have to keep more than one set of gear. That doesn't make much sense, however, because 3.1 will also include a gear rack feature.

Other helpful folks reassure me that it's necessary to maintain balance for Ulduar. I'm not convinced that a single endgame dungeon should cast a shadow on druids tanking at all levels throughout the game, though.

My most helpful friend, Miss Direction, reassured me that a simple change of gems would probably make up the difference once I get my Tier 7 set. I have my doubts about that, but will try to keep an optimistic outlook on the matter. I don't like the idea of my treasured Leatherbelliness™ going away.

Whatever the ultimate reason, the PTR changes are only proposals at the moment.

Leatherbelliness™ is a Whole Lot of Bull

The first time I asked my guildies about how to gear my feral tank they gave me some straightforward advice. Just stack agility and the rest will take care of itself.

Not bad advice, but sub-optimal.

In 2009, feral tanks need more than avoidance to perform at the top of their game. Especially since diminishing returns on avoidance were confirmed in Wrath of the Lich King. I have since spent a lot of time crawling through posts by Ciderhelm and Corbusier on TankSpot & Elitist Jerks, and have come to trust their wisdom regarding Effective Health.

The combination of wit, mitigation, avoidance, and a nigh-insurmountable hit point total is something I call Leatherbelliness™. This is just a playful term I use to describe a large Effective Health combined with a smart play style and good technique.

I won't get into the nitty gritty just yet, but Effective Health works out like this: If you have 10k health but only get hit 65% of the time, you effectively have 15,385 health. If you can reduce 10% of the damage you do take after avoidance, this number becomes 17,094 effective health.

All tanking classes have effective health--death knights and paladins can self-heal, warriors can mitigate damage through massive absorption. Since WotLK does away with crushing blow mechanics, it might seem like having big EH isn't quite as important as it used to be.

Don't be fooled. At the end of the day you get to dine on knuckle sandwiches. Twitchy melee DPS who don't grok the parry mechanics and haven't capped their expertise can still put you on the wrong end of a haste debuff with a boss through bad placement, and when you're riding on 30 or 40,000 hit points your healer will appreciate the depth of that health pool, will perform fewer overheals, and your blood pressure will remain at optimal levels as a result.

Now, that said, Leatherbelliness™ is not a slave to statistical averages. From time to time, people will ask me whether a given piece of gear is "better" than another piece of gear for tanking. You've seen it in guild chat. You know what I'm talking about. My answer is consistent, one learned from my time as a software engineer.

It depends.

What's the situation? Every engineer knows that there's a tool for every job. Different jobs call for different tools. Is there one single set of gear that's going to be "best" for feral tanking?

Nope.

With that in mind, I go for maximal Effective Health on average, but I keep an arsenal of specialty options at my fingertips. Knowing when to ditch some health for dodge or increased threat generation, and being able to do so with one click because you came prepared, is Leatherbelliness™ at its best.

I learned to play WoW on a warrior, which taught me all about the importance of knowing what gear to use in which situation. For about six months I maintained custom gear swapping macros that were tuned to the stance I was in as a warrior. When I flipped into defensive stance, out came the shield, defense, and expertise gear. Those lessons carried over seamlessly when I started playing my feral druid (and started using Outfitter, thank the skies). To this day, when I switch into caster form, my mana pool explodes, cat form drops me into my strength, crit and AP gear, and when I go from either to Dire Bear form, it sets off alarms on my MikScrollingBattleText, because my max health in Cat Form is about 25% of my total when wearing my tanking kit in Dire Bear form.

This continues to freak out my healer, by the way.

In WoW, as much as anywhere, the clothes make the (man|bear|tank). So, my first piece of advice is to get big bags and the Outfitter addon. Especially while you're questing and leveling, you're going to need utility in cat and caster form. Having the flexibility to quickly swap gear will allow you to truly specialize for tanking while you are in Bear and Dire Bear form, instead of trying to find the one-size-fits-all gear set that just does not exist.

By Way of Introduction

Hello and welcome to Khorium Powered Tank Engine. My name is Etaiu, and I will be your host. I started this site in order to provide a much-needed resources for feral tanks. I've read other feral tank blogs (they know who they are) and found them wanting in focus. By too-often straying from its core competency, a blog can quickly devolve into a personal soap box.

So, in keeping with my real-life and in-game engineering tendencies, I will keep the feature-creep out of this blog, and maintain a surgical focus on Engineering-augmented Feral Tanking. This is not my only blog, so you the reader can expect an optimal amount of (zero) spillover from unrelated subjects. Some of the information I provide will be my own findings, and some will be received knowledge that I will try to independently verify or debunk.

The main purpose of this site will be twofold.

1. To develop a more comprehensive understanding of Effective Health through Mitigation, Avoidance and sheer Leatherbelliness™. Gear analysis and comparisons will play a role in this.
   
2. To illustrate sound feral tanking technique, augmented by engineering, to maximize your control in dungeon situations. Tricks of the trade, including (but not limited to) dungeon strategies, macros, and gadgetry will factor into this analysis.
   

The first duty of a tank is not to stay alive, but to keep their party alive and buy them time to bring down the quarry. Staying alive is merely a habit in keeping with that primary goal. Threat generation, agg management, communication, mob handling, situational awareness, and wipe recovery are all equally important components of a tank's arsenal.