Musk loses a top talent at xAI as the creator of Grok 4 suddenly quits, and a long post reveals the most exciting startup secrets.

Another co-founder of xAI has officially announced his departure! Igor Babuschkin, the father of AlphaStar, published a long post to say goodbye, recalling leading a team to build the world's most powerful supercomputer in 120 days of intense work. Elon Musk personally expressed his gratitude, saying, "Without you, there would be no xAI today."

Igor Babuschkin, a co-founder of xAI, has officially announced his departure to start a new venture!

On his last day at xAI, he used a long post to look back on the day in early 2023 when he met Elon -

We talked for hours, discussing the future and infinite possibilities of AI. We both believed that the world needed a new type of AI company with a different mission.

In two years, they achieved it and presented an amazing result.

They not only built the world's largest AI supercomputer, Colossus, in 120 days under extreme conditions but also trained Grok 4, a multi - modal model comparable to those of OpenAI and Google DeepMind.

Now, the departure of AI expert Igor Babuschkin officially marks the end of a chapter in xAI's journey.

Next, he is going to establish a venture capital firm called Babuschkin Ventures to start a new journey.

Below the post, Musk gratefully said, "Without you, we wouldn't be where we are today."

Another co-founder, Toby Pohlen, listed those unforgettable moments:

• On the first day, we flew directly to Austin;
• We all worked like crazy to develop Grok - 1;
• We reviewed a total of fifteen thousand applications in one day;
• There was also that Sunday at the winery with Kyle and Lilly when we launched the open - source website and code repository for Grok - 1...

"I'm very grateful to you for calling me to join the team in early 2023. I'll always be thankful for that."

What kind of person is Igor Babuschkin himself, and what core contributions did he make during his time at xAI?

The father of AlphaStar, built the largest AI supercomputer in 120 days

Before founding xAI, Igor worked as a senior R & D engineer at Google DeepMind.

During his tenure, he led the AlphaStar project, an AI system developed for "StarCraft". Through reinforcement learning training, it finally defeated human players and achieved a Grandmaster - level combat ability.

He also participated in the development of the WaveNet voice system, significantly improving the naturalness and quality of speech synthesis.

After two years at Google, Igor joined OpenAI and participated in the R & D of core technologies behind ChatGPT, such as GPT - 4. Then he returned to Google.

Igor's work experience at Google DeepMind and OpenAI gave him rich experience in deep learning and architecture design.

He also has a strong background in physics. He once worked at the Large Hadron Collider and later switched to this field due to his passion for large models and AI.

According to his personal information, he obtained a master's degree in physics from the Technical University of Dortmund, Germany.

During his time at xAI, Igor led the construction of the Memphis supercomputing cluster - Colossus, providing support for the large - scale training of Grok.

In addition, in terms of models, he also led and supported the R & D of Grok from its initial version to multiple iterations. Now, Grok 4 has become a top - tier model that can compete with Gemini 2.5 and GPT - 5.

At the Grok 4 launch event, Elon Musk previewed the upcoming release plan for the next few months.

From now on, there will be one less key member for xAI's future historical releases.

Departure post: Victory at 4:20 a.m.

Creating AI that can drive human progress is my lifelong dream.

After the dissolution of the Soviet Union, my parents left the Russian Federation to seek a better life for their children.

As immigrants, life was not always smooth. But despite the hardships, my parents always believed in the priceless value of human values: courage, empathy, and curiosity to explore the world.

As a child, I greatly admired scientists like Richard Feynman and Max Planck, who continuously pushed the boundaries of physics to understand the universe.

As a doctoral student in particle physics at CERN, I was excited to be involved in this mission.

However, the path to exploring new physics became increasingly difficult. The colliders were getting bigger, but there were few new discoveries.

So I began to think that the key to unlocking the mysteries of the universe might not be a bigger collider, but superintelligence.

Can AI develop a unified theory of quantum gravity? Can AI prove the Riemann hypothesis?

By early 2023, I was convinced that we were close to the secret of creating superintelligence.

I sensed the trend: soon, the reasoning ability of AI would surpass that of humans. But how could we ensure that this technology was used for good?

Elon had been warning about the risks of powerful AI for years. Elon and I realized that we shared a common vision of using AI to benefit humanity.

Therefore, we recruited more like - minded engineers and started xAI.

The early days of xAI were full of challenges.

Some people were skeptical, saying that we were too late to enter the game and it was impossible to build a top - tier AI company from scratch. But we believed that we could turn the impossible into possible.

Building from scratch required a lot of hands - on work:

• At first, I built many basic tools within the company to start and manage training tasks.
• Later, I was responsible for most of the company's engineering projects, including infrastructure, products, and applied AI.

Everyone at xAI was extremely enthusiastic. Our team worked hard and built the Memphis supercomputing cluster at an amazing speed, and delivered cutting - edge models at the fastest pace in history.

I learned two valuable lessons from Elon:

• First, be brave enough to "roll up your sleeves" and solve technical problems hands - on;
• Second, have an almost crazy sense of urgency.

xAI's execution speed was incredibly fast.

Industry veterans said that it was impossible to build the Memphis supercomputing cluster in 120 days. But we believed that we could turn the impossible into possible.

Our goal was to get the training facilities running at full scale on the Memphis cluster as soon as possible.

As the 120 - day deadline approached, we were troubled by RDMA communication problems between machines. So Elon decided to fly to the data center in person, and we followed.

Our infrastructure team arrived in Memphis at midnight and immediately started working.

After checking tens of thousands of lines of lspci output line by line, we finally located an incorrect BIOS setting - which was the root cause of the problem.

Elon stayed with us working late into the night. When the training task finally ran successfully, Elon posted about our victory at "4:20 a.m.", making us burst into laughter.

I'll never forget the excitement of the adrenaline rush that night and the emotional bond of us all being in the same boat. When we went to bed, we felt like we were living in the most exciting moment of our lives.

I love everyone in the xAI family deeply.

Our team is so special - you are the most focused and dedicated partners I've ever worked with. It's not easy to catch up to the industry forefront so quickly.

All of this is due to the perseverance and team spirit of every member.

Thank you to everyone who joined me on this journey. Your contributions, time, and sacrifices are extremely precious, and I hereby express my highest respect.

I'll always remember the days and nights we worked late into the night. I'll never forget your efforts and sacrifices.

Today, as I drove away, I felt like a proud parent slowly driving away after seeing my child off to college. My heart was filled with mixed emotions, with both tears of joy and sincere applause for the company's growth and maturity.

As I start a new chapter in my life, I'm often inspired by my parents' story of immigrating to seek a better world for their descendants.

Recently, I had dinner with Max Tegmark, the founder of the Future of Life Institute. He showed me a picture of his young son and asked me, "How can we develop AI safely to ensure that our children can thrive?" His question really touched me.

Early in my career, I was the technical leader of the DeepMind Alphastar StarCraft agent and witnessed the powerful force of reinforcement learning after scaling.

As cutting - edge models become more "agent - like" over longer time scales and broader task scopes, they will have increasingly powerful capabilities. And this makes researching and promoting AI safety extremely important.

I hope to continue my mission of creating AI that is safe and beneficial to humanity.

Here, I announce the establishment of Babuschkin Ventures to support AI safety research and invest in startups of AI and AI agent systems that drive human progress and unlock the mysteries of the universe.

The singularity is approaching, but the future of humanity is bright!

Of the 12 - member founding team, only 9 remain

On July 13, 2023, Elon Musk publicly announced the establishment of the new xAI company, aiming to explore the essence of the universe and create a super AI that