The crowdfunding campaign for Star Citizen, the upcoming PC sim from Wing Commander creator Chris Roberts, continues to soar. The campaign has now raised more than $55 million (up from $51 million in mid-August), which is "unthinkable" for Roberts.

"Two years ago, the idea that a group of people who love space sims, PC gaming, and the promise of a huge new universe to adventure around in could unite to raise $55 million to fund a game was unthinkable," he said in a post to the game's website.

The game is the most crowdfunded project of any kind in history. Its original Kickstarter campaign went live in October 2012, wrapping up with $2.1 million, meaning the overwhelming majority of funds have come via ship sales and other contributions made through its website in the time since.

Star Citizen fans who contributed to the campaign before it reached $55 million will receive the Preacher Armament Inquisition XXII ship upgrade. This will be available through a future update to the game's Arena Commander mode. The next stretch goal will be a new ship, and players can vote on which one they want today through a poll on the game's website.

Also in the blog post, Roberts said developer Cloud Imperium Games hasn't shut off crowdfunding yet (if it ever does) because Star Citizen is anything but a "normal" game.

"It's not being developed like a normal game and it's not being funded like a normal game," he said. "I've had to toss aside a lot of my knowledge from the old way of developing and embrace a completely new world. There is no publisher. There is no venture capitalist wanting a massive return in three years. There is no need to cram the game onto a disc and hope we got it all right."

"Star Citizen is not the type of game that will be played for a few weeks, then put on a shelf to gather dust," he added. "Instead of building a game in secrecy we can be fully open with you as a community who have made this game possible. We can involve the future player base in the creative feedback loop as we develop and iterate core systems. As a group, we are all involved and united in our quest to make the best game possible."

Roberts also explains that all the money--$55 million and counting--is being poured into Star Citizen to build out and expand what he has in mind for the game's vision. "Funding to date has allowed us to go so far beyond what I thought was possible in 2012," he said. "You're still getting that game, no question, but it will be all the richer and so much more immersive because of the additional funding."

He added that Cloud Imperium games has a "healthy cash reserve" on hand so that if funding ended tomorrow, the company could still deliver Star Citizen to backers. In addition, he revealed that there are now more than 280 people working on Star Citizen, which counts in-house staffers and freelancers. This is up from 250 just a few months ago.

But along with Star Citizen's massive crowdfunding tally come concerns about "feature creep." That's the idea that the constant addition of new gameplay features could push the game's release date out further. Roberts said this isn't an issue for Star Citizen.

"I would say that this would be fair criticism if we were delivering this game at retail and on disc," he said. "However, we are online and already pushing out builds, well before Star Citizen reaches what anyone would consider a 'finished' stage. We want to make the best damn space sim ever, and with your continued support I know we will."

For more on Star Citizen and Roberts himself, check out part one and part two of GameSpot's interview with the legendary designer.

Eddie Makuch is a news editor at GameSpot, and you can follow him on Twitter @EddieMakuch

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