Just because Elon Musk is building his own private space program and the automobile of the future doesn’t mean he has no time for games.

The SpaceX and Tesla chief executive officer took to online-aggregation site Reddit today to do a question-and-answer session with the public. In his answers, he gave a shoutout to taking showers, his elementary-school principal, and Winston Churchill — but he also gave a thumbs up to some video games.

Musk is a self-taught rocket scientist, and he had a hand in designing the reusable rockets that are the heart of SpaceX. That led one Reddit poster to ask the technologist if he had played the outer-space flight simulator Kerbal Space Program, which enables people to build and fly their own interplanetary crafts.

It turns out that Musk has not only played it — he deeply enjoys it.

“Kerbal is awesome,” he said in response.

Another Reddit poster took the opportunity to ask Musk about his favorite game.

“Hard to pick a favorite,” Musk wrote. “I tend to like [shooters] with a story, like Bioshock, Fallout, or Mass Effect, but [I am] also a big fan of Civ and Warcraft.”

It’s not surprising that a guy who has invested so much in sci-fi like technologies would have an appreciation for games like Fallout and Mass Effect that deal with the future and space travel. But Musk’s fondness for Civilization makes even more sense.

Civilization is a turn-based strategy game where you start off as a tiny band of prehistoric settlers who must expand and exploit resources. As the player progresses in Civ, they move through historical epochs until they reach the present day. A big part of accomplishing that is by researching new ideas, theories, and technologies that unlock even more ideas, theories, and technologies as part of what the game calls the “tech tree.”

In a separate answer, Musk revealed how his feelings toward knowledge reflect how Civilization represents human progress.

“It is important to view knowledge as sort of a semantic tree,” he wrote. “Make sure you understand the fundamental principles — the trunk and big branches, before you get into the leaves/details, or there is nothing for them to hang on to.”

Today, Musk was overseeing SpaceX’s latest rocket launch, but the company had to abort due to a malfunctioning component.