Chris Roberts' Star Citizen, the spiritual successor to the Wing Commander series and unprecedented crowdfunding success, has encountered serious technical and gameplay issues that will indefinitely delay one of the game's key modules, a first-person shooter called Star Marine.

Star Citizen is a lavish space combat simulation comprised of several interconnected modules. The hangar module and the multiplayer dogfighting module, called Arena Commander, have been available for some time now. In March of this year, Roberts revealed that three more modules would released in 2015. First would come Star Marine and a terrestrial, social module called Planetside. Later, the first episode of the single-player campaign called Squadron 42 would be released, as well as the MMO-like persistent universe.

All of these releases would eventually lead to the commercial launch of Star Citizen in 2016.

But the latest release of Star Citizen's playable beta, dubbed update 1.2, is late. The planned spring release of Star Marine and Planetside has come and gone, with no word on what was causing the delay. Until this weekend.

In a letter from Roberts, dated June 27, he cited "technical and gameplay-related issues" that will delay the Star Marine module indefinitely.

"We feel the current build doesn’t feel like it lives up to the standards we’ve want to achieve with Star Citizen [sic]," Roberts wrote. "There are several issues that will need additional time in order to deliver the first iteration of the gameplay we want you to experience.

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"When will we see Star Marine? Tonight, I don’t have an absolute answer for you. What I will tell you is that we know exactly what we have to do, and we’re already well on our way to doing it."

Star Citizen's development so far has been unusual in that it's spread across multiple teams, all over the world with each team focused on a specific module. While there's some overlap, the team dedicated to the FPS module accounts for roughly 15 percent of the total workforce, Roberts said. And while they've mostly been silo'd, their troubles will have some impact on the overall release schedule of the game. But that impact, Roberts said, will be hard to quantify.

"I don’t want to say that there is no impact," Roberts wrote. "Integrating the FPS properly will help move every part of Star Citizen forward, as the tech will help form the blood and sinews of the whole game… but I can’t stress enough that two additional months spent on Star Marine are not the same thing as two months of a delay for Star Citizen. The persistent universe team in Austin is still building brilliant new worlds, the ship team in Santa Monica is coming up with great concepts and integrating existing ships in preparation for future Arena Commander updates… and of course the Squadron 42 team in the UK is full speed ahead on the single player adventure."

The biggest challenge, Roberts said, would be stripping the Star Marine content from the latest build.

"To that end, we are going to investigate releasing a build with Star Marine disabled that would allow you to experience some of the changes and updates we’ve made over the last few months to the core code base. There are some technical challenges in doing this, and it won’t happen overnight… but I feel that it’s incredibly important to do because we need to test with the public, we need to collect your feedback and frankly we need to continue proving that we’re working on what you care about."