This is a much-needed change with some fascinating implications. To recap, hunters will no longer use mana, they will use "focus" instead, which is just another word for energy with slightly different regen mechanics. This was, of course, the original plan in WoW: Hunters used focus, which they only regenerated by standing perfectly still.

This has fascinating implications for hunter shot design (and perhaps pvp), and also helps highlight how movement impacts the different resource systems differently. This is the second time that they have explicitly limited hunter resource regeneration in a specific way, and it is certainly deliberate.

At the end of my post I actually look broadly at the different resources and how movement/interrupt affects them all.

For the full post, click on the link to continue:

There are two interesting implications to hunters having focus instead of mana:

Cooldowns disappear

One is that they are, of course, going to remove many or all of the cooldowns on the hunter abilities.

Remember that, since mana isn't a pacing mechanism (read On Resource Systems if you need a refresher), it's fuel, there is nothing stopping mana-users from doing damage every GCD except cast times and cooldowns/dots. Since hunters are designed more like a melee, with more instant and short-cast abilities, they are designed heavily around cooldowns and dots in order to limit their DPS.

It will force more interesting hunter shot design: cooldowns are a cheap way of forcing you to use multiple abilities, since you don't have to make an ability interesting or worth casting, you just have to make everything else be on cooldown. This is part of the reason you get things like Ret Paladins being played just as well by a /castrandom macro as by a real player (within 1.5%.)

I'm curious the intentions: are hunters intended to become a gcd-bound class? I imagine the impetus to weave Steady Shot in will be to keep your mana regen up -- perhaps via a short buff on you, to force a Steady Shot once every 10 seconds. Or it may be a "focus lifetap", giving you an injection of focus, so you can pull in as much as you need and then switch to higher-damage shots.

Will they make some shots have a longer 'cast' to force a mixup? That would make sense, as well as making a good way of distinguishing between pve and pvp abilities. It might be unpopular though, making hunters feel too much like a caster.

This could also lead to higher up-front PvP burst, depending on the implementations. You can chain a bunch of cooldowns together (like Ret Paladins) and achieve a high up front burst. But if you're designed to have only one "big hit" spell that used to be on a cooldown, being able to chain it back to back could actually increase burst. A lot will depend on ratios and costs, we won't know until 4.0 gets underway.

It could also lead to lower PvP damage: forcing hunters to stand still too much may result in either too-low PvP dps, forcing Blizzard to increase the non-steady-shot focus regen rate so much that hunters become even stronger in movement/target-switching fights in pve (where they are already the best class.)

Resources and Movement

The other is something I had noticed with Aspect of the Viper but hadn't realized the full implications until now: with both focus and AotV, hunters are designed to regen less while not DPS'ing.

Reviewing my other post On Resource Systems here briefly: cast times are the same as energy regen. A 4-second cast equals a 40-energy ability. But there are several key differences between cast times and energy:

1. Cast times can be hasted in 3.x, energy regen can't, and
2. Energy regen can be done while mobile.

It's this second one, of course, that is interesting. Basically a rogue who is moving from target to target, or who is chasing an escaping caster is amortizing his cast time by continuing to regen energy while he runs. He is capped at 100, of course, but as long as he's below 100 he can use his dps "dead time" to, in essence, start his cast while he moves.

What does this have to do with hunters? AotV regenned some base mana, just like focus does But when a hunter is DPS'ing, AotV returns more mana. Similarly, when a hunter is casting Steady Shot, the hunter's focus regen rate goes from 7 to 12.

As an aside, this is also how TBC-era shadow priests worked because their mana regen was so high when casting -- hunters are not unique. When Blizzard decreased their mana regen and boosted their DPS, they also increased their mana efficiency.

This "cast on the move" represents an effort by Blizzard, I am certain, to reduce the 'costs' for energy and rune classes when having to move from target to target: they get back some of the DPS they lost while moving making movement and interrupts less painful even if they have further to run.

A specific example: If I am a rogue, and am at 20 energy, I have to wait two more seconds to gain 20 more energy so I can sinister strike. If I have to move for four seconds, however, I will be at 60 energy and be able to sinister strike immediately when I reach my target again and still have 20 energy 'banked.' I only lose autoattack time in this ideal-world scenario.

Hunters are a ranged class, so while they need to move out of fire, if it's just a target switch they do not have to run as far as melee. Therefore, I believe, the design of "focus regenerates more quickly while you dps" is very deliberate. Because they are ranged, Blizzard doesn't want hunters on par with melee in terms of amortizing the cast-time during movement (in either pvp or pve.)

DK's have runes which regenerate at a set rate like rogues, but runic power doesn't continue to build as the DK moves (although they have some ranged damaging moves they can use if they need to.)

Rage-based classes don't lose rage while moving, but they don't gain much either. Their abilities are instant, so they don't lose "cast time", but they don't have the advantage that the energy-based classes do when moving from target to target.

Casters interrupt their cast when they have to move unexpectedly, losing any cast time already spent. This effect is worse, obviously, the longer the casts the class has. Some casters have instant casts to mitigate this loss of cast time. If I were designing the world, those with longer casts would have more and more-usable instants to compensate for this.

Melee all lose autoattacks and procs while moving, of course, and hunters lose autoshot when moving as well. I'm not trying to imply that there's no dps loss, just that there's some clever loss-mitigation visible when you view the resources in terms of the cast-time model.

Note that I'm glossing over some things here like Slice and Dice dropping. But Scorch is also on a 30-second timer. Procs can be lost, etc. This is just focusing on the design of the resource systems.