On to Deathknight Combat Resources. First, a bit of self-definied terminology: by Combat Resources I mean the 'power' that your character has, as in Rage, Mana, Energy or Focus (if you are a pet... *pats hunter pets*). Combat Resources define what abilities you can use, when you can use them and how powerful they are when you use them, and for this reason it makes sense to include the Roguish/Druidic Combo Points mechanic under the umbrella of 'Combat Resources'.
By their very nature combat resources are a limiting, rather than empowering factor to gameplay. Without these mechanics you'd be able to play your most powerful ability almost endlessly, heal without limitation, generate aggro without a care; their design and implementation is crucial to game balance.
So, on to Deathknights. Their combat resources have been announced and so they can be analysed with less uncertainty than their skills and talents (which are still very much in a stage of flux). And so, what are they?
Runes: A resource which appears to be a subtle adaptation of Energy into a hybrid model. Like Energy the mechanic limits the number of actions you can perform over a given time period. Unlike Energy (or Rage or Mana) it is not generic for all spells/abilities. There are three Rune types each of which broadly controls a different aspect of the class -You can have up-to six runes of any type at one time, the configuration switching as you switch weapon. The types of Runes you have chosen to make available will largely speaking define your role, more Blood = Melee DPS, majority Frost = tanking etc. Also, talents which provide a generic 'Rune' to be used with any DK spell/ability should be expected, though they may be too unreliable to use. Blood - Predominantly control the usage of DPS abilities. Frost - Control Frost Spells and Abilities, mainly used in tanking but includes other utility functions. Unholy- Control the Shadow Abilities and diseases, generally pvp-oriented but expect to see significant group/raid utility here. Runic Power: A resource akin to a subtle combination of Combo Points and Rage. It builds up to a maximum Power of 100 as you deal damage through auto-attacks or other abilities. Activated abilities always (at this stage) use 100% of the RP you have built up and have potency equivalent to the amount of RP used. For damaging abilities this resource is likely to become less important as gear/attributes scale, though this may change.
What does this system mean design-wise? Well, it attempts to solve the single largest issue in hybrid design - how to balance a hybrid such that it is not overly powerful in any two or three roles at one time. Druids and Priests are balanced in this way by Forms locking out certain aspects of the class, Paladins and Shaman by making gear and talents integral to being viable in any given role. This limits just how much of a hybrid any class can be - Rohan describes them as 'modal hybrids', classes that can fulfil any role, but only one during any given encounter. The exception of course is Feral Druids due to the strength and efficiency of the Feral Tree. Deathknight resource design however is much more fluid in their ability to perform multiple roles. Whilst largely being defined by their talent spec, the Runic system allows them a certain amount of on-the-fly specialisation previously the sole purview of Form-based hybrids, or retaining the hybridity of the non-form archetype and relying on gear to scale your viability. The devil is in the detail, but it is certain that it allows a much wider range of mechanics (DPS, snares, stuns, dots etc.) to be available base-line than that of the classes it most resembles - Paladins and Shaman. Could this be the best of both worlds?
Does this system sound Heroic? Well, it's unique but it does combine elements of other game mechanics. On the flip side it seems significantly more complex than other systems currently in the game and hence should require a whole lot more skill to manage. In all honesty that's good enough for me when it comes to defining it as 'Heroic' in that it provides something new, taxing and rewarding to the game experience over and above current resource mechanics.
Not everything is set in stone though, Hunter mechanics changed late in WoW Beta and the same may happen to DK's if their system is found to be sufficiently flawed at this stage.
In Part 3 I'll talk about class mechanics, and how they may define the DK to be truly heroic or just another class. Comparisons to the Beta Paladin may be made... consider yourself warned.