Sean Murray had been working through the night when CNBC met him during the late morning at PlayStation's London headquarters last Wednesday.
His team at Hello Games where he is managing director had been putting the final touches on the update of "No Man's Sky", the much-hyped game that was released in the U.S. on Tuesday.
It's an ambitious project. "No Man's Sky" is built using a technique known as "procedural generation" – essentially an algorithm that creates the game's world as a player moves through it. Traditionally a game studio would have to draw intricate designs in order to create a fixed number of virtual worlds, a labor-intensive process that could take hundreds of designers.
But the world in "No Man's Sky" creates itself and even Murray hasn't seen what the entire universe has to hold for the player.
"We haven't seen most of what this universe can create, so in this really real way we are starting players off and letting them go out and explore for us," Murray told CNBC.
The universe of "No Man's Sky" is gigantic with over 18 quintillion – or 18,446,744,073,709,551,616 – possible planets to visit. People can travel through the universe, upgrading weapons and spaceships, discovering new plant species, animals or even planets then naming them. This is then added to the game's server and the user's name is forever etched in "No Man's Sky" history.
So far this has led to some funny results as Murray posted online in a Tweet.
Users can also trade minerals or items they find and fight or loot native creatures on planets they discover. Players need to survive and keep their character alive.
The game might sound pointless, but Murray said that players looking for an end can get one by travelling to the center of the universe. There they will get a reward.
"That journey to the center, as you make that, you will find the universe you are in becomes more and more strange and difficult to progress, like any normal game ,there is a linear pattern you can take," Murray told CNBC.
"No Man's Sky" is being released amid much hype which is always the danger for big releases. The key for "No Man's Sky" is its ability to keep players hooked in the expansive universe, analysts said.
"Its success really depends on how they build the survival aspect and the trading aspects of the game and what you can discover, how you can upgrade, how that experience develops over time," Piers Harding-Rolls, head of games at IHS, told CNBC by phone.
"That balance between discovery, exportability and survival is key to the game."
Murray compared "No Man's Sky" to Minecraft, a game where players need to build worlds but there is no real closure, something he also sees in the latest hit "Pokemon Go".
"'Pokemon' the original was so well-defined, with a beginning and end point and very obvious goals and rewards within the game. 'Pokemon Go', why is everyone playing it? It's not as defined and you are doing it because it's fun. It's allowing people to play games the way they want them," Murray explained.
It's not Murray's first game. He left Electronic Arts several years ago to found Hello Games and ended up selling his house along the way to complete "Joe Danger" which was released on the PlayStation in 2010.
The money from this game was pumped into "No Man's Sky", but Murray said he has never actually worked out how much the game cost to make.
So-called procedural gaming is the key to the expansiveness of the game and visiting every planet that could be created is impossible, unless you have a few billion years to spare.
"If a new planet in 'No Man's Sky' was discovered every second, it would take 584 billion years for them all to be discovered," Murray said
"In terms of beating the game, it's not really an option unless you're going to hand it down from generation to generation."
But the kind of algorithmic development being used in "No Man's Sky" could be key for future studios. Hello Games is small, counting a dozen or so developers among its ranks. In comparison, game studios like Naughty Dog which made the extremely popular "Unchartered" series for the PlayStation, often have hundreds of people working on the game. Because each planet did not need to be designed by hand, it allowed the small indie studio to create such a giant game.
Procedural game making could cut costs and allow smaller studios to compete with the giants, but Murray does not expect every game from now on to be developed using this technique.
"I don't know it will necessarily be the future of games but it will definitely be part of that," he said.
However, the game's development hasn't been smooth. As well as being plagued by delays, earlier this year Hello Games settled a legal challenge with British broadcaster Sky which claimed the video game was infringing its copyright by using "Sky" in its title.
Hello Games was also accused of using an algorithm developed by someone else to create their game. The so-called "superformula" was developed by Johan Gielis, the inventor of this single algorithm which can shift shapes and be used in many different places. But Murray said that Gielis' "superformula" is one line of code whereas "No Man's Sky" uses "well over a million lines of code".
The game has finally hit the market, but reviewers only received their copy on Monday, giving them just a few hours to play. Initial thoughts appear to praise the technical complexity of "No Man's Sky", but also question the monotony of constantly looking around then having to find some more minerals to keep your character alive and repair your spaceship.
"Even a few hours in, however, there comes a point where the loop of seeking and acquiring gear begins to sag, and the vastness of the galaxy sinks in," Gamespot wrote. IGN added that the game has "has done little to set itself apart".
But "No Man's Sky" was never meant to be played in a day, with Murray telling CNBC that it could take tens of hours to get to the center of the universe. Besides, that's not the point of the game, which places so much emphasis on exploration, and the longer people play, the more reward they get.
"These problems seem to be fading the further into 'No Man's Sky' that I get," a reviewer for Polygon wrote.
With "No Man's Sky" now available to PlayStation users in the U.S. and Europe and a PC version to come on Friday, Murray is looking to the future of the game. Continuous updates are likely to happen Murray said, which could be crucial for keeping this game fresh.
But could this game also be coming in a virtual reality (VR) form? PlayStation is launching a VR headset, slated for release later this year. Murray said VR is an interesting game form, but did not confirm if there would be a VR version of "No Man's Sky".
"I think VR is super interesting and we played about with it and things like that. Like I was saying, VR is definitely a part of the future. For No Man's Sky, we are not announcing anything, but I think it would be a super cool thing to wander around some of our procedurally generated universe (in VR), that's very science fiction."