The Design & Development article series premiered on the D&D website back in September 2005, and has been a staple ever since. With the approach of 4th Edition, and our designers and developers focused on the new edition, this column will be the primary vehicle for 4th Edition coverage. We’ll not only give you peeks at what’s forthcoming, but also the “how” and “why.”

Keep in mind that the game is still in a state of flux, as refinements are made by our design and development staff. You’re getting a look behind the curtain at game design in progress, so enjoy, and feel free to send your comments to dndinsider@wizards.com.

The warlock wasn't part of the adventuring party we originally pictured stepping out of the first 4th Edition Players Handbook. As you might expect, the original party included most all the incumbents, with sorcerers and bards alongside wizards and monks.

But the warlock was in our thoughts. Coming out of Complete Arcane, the class's chief innovation had been its eldritch blast ability, which provided unlimited arcane firepower round after round after round. After some initial shock, everyone admitted that the warlock's eldritch blast didn't break the game. The class's ability to maintain relevant arcane attack power, instead of running out of finite resources like a wizard, had a great deal of influence on our early thoughts about 4th Edition. We understood that the warlock didn't have to be the exception. All of our classes might be improved by having abilities they could count on all day long.

Fast forward a couple of drafts into the future. We'd started understanding that our power-rich approach to the classes meant that we almost certainly wouldn't be launching with every class we might want to. Our understanding of the party roles indicates that the sorcerer and the wizard might very well be standing on each other's toes and pointy hats. Then, once we saw the concept art Bill O'Connor provided for tieflings, we knew that we had to commit to including tieflings as a PC race, rather than just hopeful it would work out (more on that in a future Design & Development column).

And what class would tieflings naturally gravitate to? A class that acquired scary powers by negotiating , pacts with shadowy, infenral, or feral patrons? That worked for us. But what we didn't know at the time was how dramatically the warlock class would improve as we progressed through design. Of all the classes, the warlock has made the greatest strides from its initial concept to its final execution. In truth, we've been aided by the fact that the class doesn't have a weighty existing legacy. There aren't thousands of D&D players who have a solid and well-reasoned idea of exactly what a warlock's powers should accomplish. Whenever we came up with something cool and flavorful, we felt entirely free to try it out -- instead of qualifiedly free, as we often felt with several other classes.

Tieflings begin with a backstory of splintering betrayals and stolen power. Warlocks carry on with a fundamental choice of a pact with one of three varieties of supernatural patron. I'm leaving the specific pacts out of this, but I will say that the pacts provide direct benefits when you send an enemy you've marked to their afterlife reward; your patrons show their gratitude by giving you a Boon of Souls. And when you play a warlock, you have the tools to put your enemies away. Rather than relying only on eldritch blast, you'll also have an arsenal of curses (send enemy directly to hell for a round, then bring them back in more pieces), conjurations (maws -- connected to beings that remain thankfully off-screen -- materialize to chew your enemies), and movement powers (teleport and turn invisible, anyone?) to get you out of the trouble you're surely going to get yourself into.

From the perspective of lead designer, it's easy to see when a class is working out. I just have to notice the ease with which the designers and developers create cool mechanics for it. The warlock is feeling no pain, in contrast to her future enemies.