Rob Pardo, chief creative officer at Blizzard Entertainment and one of the lead designers of World of Warcraft, announced he's leaving the company today.

"After 17 years at Blizzard, with long and careful contemplation, I have made a difficult and bittersweet but ultimately exciting decision to pursue the next chapter in my life and career," Pardo wrote in a farewell message.

Pardo, 44, joined Blizzard in 1997 after a stint at Interplay. His game design credits include the original StarCraft, StarCraft: Brood War, Warcraft 3, Diablo 3 and more. Prior to being named chief creative officer, he held the position of executive vice president of game design at Blizzard.

In his goodbye post on Battle.net, Pardo said he's not ready to announce what his post-Blizzard plans are just yet.

"I'm looking forward to new challenges in my career, but I will always cherish the time I spent with you all and the amazing and collaborative teams at Blizzard," Pardo wrote. "It was both satisfying and humbling, and it made me a better developer and a better person. I look forward to playing Blizzard games as a player for many years to come. Most important, now I have plenty of time to learn how to build a competitive Hearthstone deck.

"As to what I will be doing next, I don't have an answer for you yet . . . but I will 'when it's ready.' My priorities are to enjoy the summer with my family, play plenty of games, and think about what's next. The game industry is such an exciting place right now with PC gaming thriving, the new consoles, mobile games, and virtual reality becoming an actual reality. It's like having an empty quest log and going into a new zone for the first time."

Pardo was working on the next expansion to World of Warcraft, Warlords of Draenor, which is expected to arrive later this year. Blizzard has not named a replacement for Pardo.

Polygon has reached out to Blizzard Entertainment for additional details.