Elon Musk returned to SXSW five years after his first appearance at the festival in a surprise Q&A announced the morning of the event. Musk sat down in front of a packed audience and entertained questions about everything from renewable energy, to space travel, to a cowboy hat donning performance of “My Little Buttercup” with his brother, Kimbal.

Nearly a month after the successful launch of the Falcon Heavy, Musk is optimistic about the future of interplanetary travel, especially the prospect of developing a human society on Mars.

“There’s explosion of entrepreneurial opportunity because Mars will need anything from to pizza joints, to night clubs,” Musk said.  “Mars should really have great bars– Mars Bars.”

What others see as science fiction, Musk sees as possibility, which was the inspiration for the famous payload of the Falcon Heavy: a crash dummy riding in Musk’s Tesla, listening to David Bowie’s “Starman” on an infinite loop.

“We wanted the public to get excited,” Musk said. “The goal of this was to inspire you and to make you believe as people did in the Apollo era that anything is possible.”

Musk addressed the greatest challenge in advancing interplanetary space travel is reusability, where currently most rockets are only good for one use and cost more to make than to rebuild after one launch.

“Reusability is so fundamental to rocketry, it is the fundamental breakthrough that’s needed,” Musk said.

Next, Musk answered questions about the beginnings of Tesla and SpaceX. For a long time, Musk was uncertain either company would yield success.

“I gave Tesla and SpaceX from the beginning a less than 10% chance of likely to succeed,” Musk said. “In the beginning I wouldn't even let my friends invest because I didn’t want them to lose their own money.”

In 2008, a year Musk described as “brutal”,  both companies were in financial turmoil and Musk only had enough money to ensure the survival of one company.  In the end, he took a risk that paid off.

“I had two choices, put it all into one company and the other would definitely die, or split it and put it in both companies and both might die,” Musk said. “If things had gone a little bit the other way, both companies would be dead.”

In regards to his latest endeavor, The Boring Company, a project dedicated to creating faster modes of land transportation through the use of tunnel systems, Musk said he spends very little time dedicated to its advancement compared to Tesla and SpaceX.

“Boring is literally 2% of time, but 20% of my tweets,” Musk said. “The tweets do not correlate to the time spent.”

The tunnel system concept began as a joke, but Musk realized the idea’s practicality after driving on the notoriously congested Interstate 405.

“After four or five years of begging people to build tunnels I was like ‘Okay, I wanna build a tunnel.’”

The company is funded completely through merchandise sales, most notably, flamethrowers.

“Thank you to anyone who's bought our flamethrower,” Musk said. “You won’t be sorry, or maybe you will?”

Lastly, Musk addressed questions about the future of artificial intelligence, a topic Musk said is both exciting and dangerous. While Musk believes that artificial intelligence will greatly improve the quality of life for many people, particularly in the form of self driving cars which he said can reduce the number of highway accidents by 45%,  he is wary of unregulated developments in artificial intelligence.

“We have to make sure the development of AI is symbiotic with humanity,” Musk said. “Mark my words, AI is far more dangerous than nukes.”

Musk then mentioned another reason why he believes colonizing Mars is important- in the event of a catastrophic World War III type situation, there needs to be a remnant of humanity to restore the status quo.

“We want to make sure that there’s a seed of civilization somewhere else, and bring civilization back,” Musk said. “I’m not predicting anything, I’m just saying give it enough time and it will happen. This has been our habit in the past.”

On that note, Musk concluded the Q&A with the song and dance number he promised to his fans on Twitter– a performance of  The Three Amigos’ “My Little Buttercup” with his guitar-playing companion and brother, Kimbal.