World of Warcraft creator Blizzard recently revealed its popular MMORPG continues to bleed subscribers. The game finished the second quarter with 5.6 million subscribers - an impressive number for most any game but a loss of 1.5 million subscribers in just three months.

World of Warcraft has had an incredible run that's far from over. It debuted in late 2004 and went on to become the best-selling PC game over the next two years. At its peak in October 2010, WoW played host to 12 million subscribers. Since that time, however, users have slowly abandoned the game.

The 5.6 million subscribers at the end of June is the lowest the game has seen since 2005. Even still, it remains the top-rated subscription-based game in the world and things could get better before they get worse.

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Blizzard is set to announce a new expansion for WoW called 'Legion'. If you recall, the company launched its current expansion - Warlords of Draenor - less than a year ago. Difficult times call for drastic measures, I suppose.

The World of Warcraft universe should also receive a decent shot in the arm next summer when Warcraft, the film adaptation of the MMORPG, hits theaters. Blizzard released a handful of early images from the movie back in May.

Regardless of what the future holds for WoW, it'll go down in history books as one of the most successful games in history and one that's generated a ton of revenue for Blizzard in the process.