LOS ANGELES -- It's something that players of modern single-player video games like "The Elder Scrolls V: Skyrim'' and "Batman: Arkham City'' might take for granted, but an effect that die-hard fans of sprawling online role-playing games such as "World of Warcraft'' and "Aion'' will surely appreciate: The characters in "Star Wars: The Old Republic'' can actually speak.

With more than 320 actors portraying more than 4,000 characters with 260,000 lines of dialogue, BioWare's "The Old Republic'' is poised to feature more voice acting than any other massively multiplayer online game in the galaxy when it launches Tuesday, and that's not even counting the thousands of beeps and boops sputtered by droids predating R2-D2.

BioWare, the Electronic Arts Inc. developer behind the "Mass Effect'' and "Dragon Age'' single-player franchises, has become synonymous with conversational gameplay that allows players to chat with other characters in the hope of unlocking missions, learning more about the plot, demonstrating morality and even forming virtual bonds -- romantic or otherwise.

The developer is taking that virtual chatter online with "Old Republic,'' which is set thousands of years before Luke Skywalker battled Darth Vader in a galaxy far, far away. Unlike most other persistent multiplayer games, "Old Republic'' is relying more on voices than written words to push its narrative forward with an unprecedented amount of spoken dialogue.

The highly anticipated "Old Republic'' has already drawn comparisons to "World of Warcraft,'' the behemoth online fantasy game from Blizzard Entertainment that boasts more than 10 million subscribers but little voice work. (''Star Wars Galaxies,'' a "Star Wars'' online game from Sony Online Entertainment, ended last week after eight years in operation.)

At the start of "Old Republic,'' players pledge allegiance to either the Republic or Empire and pick from eight character types: a bounty hunter like Boba Fett, a smuggler like Han Solo, a Jedi consular like Yoda, a Sith inquisitor like Darth Maul, a Jedi knight like Obi-Wan Kenobi, a Sith warrior like Darth Vader, an Imperial agent like Grand Moff Tarkin or a trooper.

The possibility of 16 different, highly customizable protagonists -- eight men, eight women -- hyper-speeding through a virtual universe populated with thousands of talkative characters, as well as millions of other players online, presented "The Old Republic'' developers at BioWare in Austin, Texas, and LucasArts in San Francisco with several new challenges.

"When you're doing a game like 'The Old Republic,' the acting is like cubism,'' said LucasArts voice director Will Beckman. "You have to see these characters from every angle and be able to pull it apart and put it back together. It's definitely a challenge for our voice actors. It's a unique type of acting that takes a tremendous amount of imagination.''

Unlike an animated film, the nonlinear nature of "The Old Republic'' requires the voice actors to record several different versions of dialogue, depending on whether players are moving along the light or dark sides of the Force, and because the game is ongoing, the developers are creating updates that will feature new content, including voiceovers.

"We tried to prepare the talent that this isn't a normal voiceover gig,'' said LucasArts voice producer Orion Kellogg. "Normally, actors come into the studio once or twice to record their audio. We've got 16 player characters alone doing tons of dialogue. They know they're coming back. I think they like it because they've been able to grow into their role.''

"Party of Five'' actress Lacey Chabert is among the hundreds of voices within "The Old Republic'' universe. Chabert plays a spunky slicer named Mako, who serves as a companion to players who choose to become a bounty hunter. Chabert, who has voiced dozens of animated characters, said the most challenging part of this role was tackling the sci-fi vocabulary.

"The language within the `Star Wars' universe is filled with words that I did not know how to pronounce,'' said Chabert. "Luckily, the producers have an audio library of planet names and everything `Star Wars' and how it should actually be pronounced. I always had to listen to a reference, and I'd almost always get it wrong the first time.''

Besides the English, German or French spoken in the game, "Old Republic'' features 21 different alien languages. While the sounds of species like the furry Wookies came directly from the LucasArts archives, Beckman said he crafted several new alien languages, finding inspiration from existing and dead real-world languages, as well as audio effects.

"It's a combination of having some idea of where you want to go with it, creating a base language from existing or dead languages, then creating a personality or style for that language and executing it with sound design,'' said Beckman, who also speaks Huttese as blubbery gang leader Nem'ro the Hutt -- among other alien creatures -- in "The Old Republic.''

The daunting amount of dialogue also technically tested "The Old Republic'' developers. They built a new system for organizing the audio, which was recorded in 17 different studios spanning from Los Angeles to London, and created a method of compressing the audio so that it can be easily downloaded by players when they install and update the game.

Visually, when players are gabbing away, a glowing conversation cartoon bubble appears over their avatar's head. When they team up with fellow Republic or Empire devotees and engage in conversations, each player elects a response, but what's actually uttered is randomly selected, and players who win the chance to speak earn extra points.

"It is a big game, and it's going to feel like that when players are installing it,'' said BioWare audio producer Sandee Valle. "More importantly, it's going to feel like that when you get out there and start exploring the world. Hopefully, we're going to be adding to the game regularly with new content and voice work for many, many years to come.''