Who was there: Blizzard game director Tom Chilton, who was speaking to a packed house at this GDC 2011 session on the challenges the team faced when remaking Azeroth in World of Warcraft for last year's expansion, Cataclysm.

　　Chilton wasn't happy about some of the changes in Cataclysm. What they talked about: Azeroth went through quite the makeover for last year's World of Warcraft: Cataclysm, with many familiar locales and even familiar gameplay elements changing with the new expansion. Chilton began his session by stating that planning for Cataclysm actually started during the end of development for Wrath of the Lich King, with the team at Blizzard acknowledging that some of the massively multiplayer online game's content was beginning to show its age. Chilton said that while leveling content was still meaningful for all types of players, regardless of their own personal play patterns, the game's core systems were becoming increasingly complex over time.

　　This increasing complexity isn't solely for MMO games, though, with Chilton saying this was even true for "separated" games that act as stand-alone sequels. After some time, these complex systems needed some pruning. In approaching what changes they would make with Cataclysm, Chilton said the team took the one-third approach; that is, leave one-third unchanged, add in one-third new, and improve on one-third of the current game. This, Chilton said, was a good way to keep the interest of core players without losing those elements that made them fall in love with the game.

　　Making changes--big or small--to Azeroth's various zones was, according to Chilton, one of the scariest parts of the process, because the "world" part of WOW was arguably its strongest asset. He said that Azeroth was a charming place to be in, drawing people in even from the first few zones players experienced. The richness of the world, he said, made people want to explore, and since it was so integral to the game, it became one of the most dangerous things to tinker with when it came to Cataclysm. But making changes to zones wasn't the only thing Blizzard wanted to do with the latest expansion. Just as some zones were showing their age, WOW's content and mechanics were also showing signs. WOW's content had become increasingly easy to categorize into three types of quests: kill mobs, collect items, or "FedEx quests." Cataclysm, Chilton said, was their way of introducing more variety.

　　But Chilton's critique of his own game didn't stop there. The designer said the first, "vanilla" WOW did not have great flow, with individual members of the design team just throwing in cool ideas for quests without any thought to flow. As a result, players were sent back and forth through the world, or even running out of quests in one zone and having to search for others. Chilton continued by saying that storytelling was also not outstanding, with the team often telling the story in found texts instead of showing people.

　　The revamp philosophy for Cataclysm, then, was to first prioritize which zones they would tinker with. Chilton said that Blizzard was all too aware that changing too much would delay the release of Cataclysm. At the same time, the team wanted to retain the soul of the original zones, while improving the mechanics and flow of the game and advancing the overall story.

　　Chilton then focused on the zone of Desolace as a specific example. The original Desolace was, as its name suggested, a desolate landscape, but it had problems because it was too monotonous and oppressive, and the quests to be found within it were not that well designed (the centaur war that players could get involved in was too narrow, Chilton said, while the legion presence in the area was actually more annoying than threatening). There was also poor hubbing, flow, and travel, forcing players to run across the entire zone to do any quests thanks to the locations of the hubs.

　　With Cataclysm, the team decided to do a visual upgrade as well as a story progression with the Cenarion regrowth. When it came to updating mechanics, flow, and travel within the zone, Chilton said their designers did an excellent job. But when it came to the lusher look of the new Desolace, Chilton wasn't quite as happy, saying that the changes actually lost a little bit of the soul of Desolace. "We didn't have to go against its original vibe to make the place less monotonous or oppressive."

　　The next zone Chilton focused on was Westfall, and Chilton said the team did a much better job with changing this area. Westfall, he said, had a really strong feel and vibe right from the beginning, in part thanks to the zone being the area for the culmination of the Defias storyline. But the zone did have the oldest mechanics and flow of the original game and, as a result, wasn't hubbed very well (with Sentinel Hill being "inadequate," according to Chilton). In Cataclysm, Westfall retained its overall look, with only minor Cataclysmic effect changes. The biggest change, however, was in improving quest mechanics, particularly with players having to uncover the story behind the disappearance of the Defias Brotherhood from the zone. Chilton was much more upbeat about the changes made to this zone.

　　Chilton then moved on to WOW's talent system as an example of a game system becoming too complex over time. Chilton said the game's talent system had become bloated over time thanks to numerous additions made with the previous expansions. Chilton said the original approach with Cataclysm was to add even more talents, just as they did with Lich King and Crusade, but the team soon realized that this had to stop. Chilton said a large number of talents would be overwhelming for new and returning players, and more talents wouldn't actually be beneficial, because there would only ever be a finite number of effective talent mixes available despite the number of individual powers on offer.

　　While the decision was eventually made to slightly pare back talents in Cataclysm, there was still plenty of choice that could be intimidating for a new player. Chilton said that at one stage, the team was mulling a system where the game would auto-select talents for novices, but quickly decided that making those decisions was a key part of the gameplay experience. And while they didn't implement a totally new system, Chilton did call out one game as having done it the right way and having a good selection without the complexity--Call of Duty: Modern Warfare 2. "As a choice system, this panned out a lot better than our talent system panned out," he said.

　　Quote: "We could really f*** it up."--Chilton on the hesitation the Blizzard team had when deciding to remake Azeroth in Cataclysm.

　　Takeaway: Chilton's main piece of advice for other developers attempting to make changes to their game or create sequels was to know what made the original great in the first place. He also stressed the need to pick the right changes, saying that making the wrong ones could ruin the feel of the game.