"With any luck, it would be like a year for each successive one, but that's going to be a target date, that's not a promise," Pardo noted in a Joystiq interview.
"In a lot of ways, you should think about the follow-ups as being kind of expansion sets to the original," Pardo explained. "It's just that the campaigns are not going to feel like expansions, they're going to feel like full, independent stories."
"I don't know how long it's going to take...it could be [a year or more between each one]," producer Sigaty revealed to MTV Multplayer. "We want to hit the shortest amount of time possible."
"Let's spin that in a positive light," he laughed, attributing the uncertainty to the time it takes to complete each story made and their respective in-engine cinematics. Sigaty also noted that the team has yet to discuss pricing details for the individual games.
Though Blizzard has yet to say when the PC real-time strategy trilogy will start making its way into stores, the first release, Terrans: Wings of Liberty, will feature the main Terran campaign and a Protoss mini-campaign.
The second release, Zerg: Heart of the Swarm will contain some RPG elements, with the third entry, Protoss: Legacy of the Void sporting some diplomatic gameplay.
The effects that the split will have on multiplayer have not been "set in stone," according to Sigaty, though each release may bring new units to the multiplayer portion.