The success of World of Warcraft has made it "difficult" for Blizzard to embark on a StarCraft MMO, the developer has said.

Speaking to at Games Convention in Leipzig, executive vice president of product development and Blizzard co-founder Frank Pearce said that while upcoming RTS Starcraft 2 isn't the last we've seen of the franchise, a StarCraft MMO is an "overwhelming" and "scary" thought.

When asked about the chances of a StarCraft MMO, Pearce replied: "It would be a lot of work! But the thing you have to remember about the MMO genre, especially now that the bar is set by games like World of Warcraft, WoW has been in development since, in some shape or form, 1999. There's people on the WoW team that have been on that team for nine years. So there's nine years of technology and story and content that are created. The bar for entry into the MMO genre, whether it's Blizzard or someone else, is very high as a result. So you're dealing with a market where games have nine years invested in them.

"And so to look at StarCraft and say, well we could make an MMO out of that. Well yeah, but how many years would we have to invest in it to create the quantity of content and the quality of experience that would be required to meet just the minimum standard that's set by the games that are out there right now?"

Pearce admitted that Blizzard's own success with WoW has made it very difficult for the developer to develop a StarCraft MMO.

"We've made it very difficult for ourselves and it's an overwhelming thought!" he said. "I've been there at Blizzard since we started on WoW and it's been a very long and arduous journey. And to think about taking that journey again with the StarCraft franchise is a little scary! It makes an RTS like Starcraft 2 seem very achievable."

However, Pearce added that there is plenty of scope for the StarCraft franchise to be "leveraged for any number of different genres", comments which are bound to add fuel to the fire of speculation that shelved third-person console shooter StarCraft Ghost isn't completely dead in the water.

He said: "The StarCraft universe is really rich, and it's got a lot of cool stuff in it that could be leveraged for any number of different genres. A big factor would be what the development teams want to work on. When the StarCraft 2 team is done with StarCraft 2, a factor is what they want to work on next, because the development teams plays a big role in deciding what they're going to do. So if there was a development team that was really passionate about leveraging the StarCraft universe for a different genre then that's something we would seriously consider."

You can read the rest of our interview with Blizzard's Frank Pearce right here.