Diablo III Beta Interview

Blizzard's official website is sporting an in-house Q&A with Diablo III lead content designer Kevin Martens about the impending launch of the game's beta test, the challenges involved with transitioning from closed testing to open testing, how the team goes about balancing content and difficulty, and more. If you've opted into the beta and therefore might wind up participating in it in the near future, you should definitely give this a read:
How are you approaching balancing the game's overall difficulty?

Kevin Martens: When it comes down to balancing the actual numbers, there is an expected amount of damage output that players should be able to sustain based on their level and gear. There is no absolute benchmark though, as skillful players will be able to do more damage with speed, precision, and advanced attack combos, while less experienced players will generally do less damage with more straight-forward attacks. The expected damage is a starting point to balance from. Balance must be maintained for both players types, and everyone in between, which can be tricky. Ultimately, it's going to take the game's harder difficulty modes -- Hell and Inferno -- to challenge the limits of the best Diablo III players.

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How are you approaching balancing the itemization in the game?

Kevin Martens: Itemization is part of a character's expected damage output, so that's already accounted for in the balance numbers. Runestones, however, add another layer of complexity, so we're spending a lot of time with these. In fact, we're treating each rune much like a unique skill because we want the player to think carefully about the advantages and drawbacks of each rune choice. For example, the wizard's Electrocute attack can be modified with an Obsidian Runestone to give it a shorter, wider blast radius, much like a shotgun, or it can be modified with a Crimson Runestone which decreases overall damage, but can pass through multiple targets in a longer line, making it ideal for sniping ranks of enemies. The former is a good for Wizards who are built to wade into groups of enemies, and the latter is good for Wizards who are built to stay out of range of enemy attacks and deal damage from afar. Our challenge is to offer the player this kind of choice with each skill and runestone.