Gabe Newell took part in a Reddit “ask me anything” event today, during which the knife enthusiast and Valve co-founder dropped some interesting tidbits on the community, including the fact that the developer is still working on “fully-fledged single player games” and a movie based in the Half-Life and Portal universe.

Newell also said Valve is open to revisiting the shared Half-Life/Portal universe, but with a new intellectual property.

One thing Newell didn’t discuss, as is his wont, was the future of the Half-Life franchise, specifically Half-Life 2: Episode Three and Half-Life 3. In fact, Newell joked that “The number 3 must not be said” and implored fans not to read too much into statements about past Half-Life games as predictors of the franchise’s future.

Here are some of the highlights from Newell’s Reddit AMA, which generated more than 12,000 comments:

In response to a question about Valve’s plans for its Source 2 engine

We are continuing to use Source 2 as our primary game development environment. Aside from moving Dota 2 to the engine recently, we are are using it as the foundation of some unannounced products. We would like to have everyone working on games here at Valve to eventually be using the same engine. We also intend to continue to make the Source 2 engine work available to the broad developer community as we go, and to make it available free of charge.

In response — a very vague response — to a question about whether Valve will continue the Left 4 Dead franchise

Products are usually the result of an intersection of technology that we think has traction, a group of people who want to work on that, and one of the game properties that feels like a natural playground for that set of technology and design challenges. When we decided we needed to work on markets, free to play, and user generated content, Team Fortress seemed like the right place to do that. That work ended up informing everything we did in the multiplayer space. Left 4 Dead is a good place for creating shared narratives.

When Newell says his favorite single-player game from Valve is Portal 2 (and not a Half-Life game)

The issue with Half-Life for me is that I was involved in a much higher percentage of the decisions about the games, so it's hard for me to look at them as anything other than a series of things I regret. There's no information in my response about what we'll do in the future. It's simply easier for me to be a fan of things that in which I was less directive. If you are involved in a game, everything ends up being a set of trade-offs. Anything in a game is a sacrifice of things not in the game. I just feel those more personally about Half-Life for a bunch of reasons. And Xen.

Newell’s answers to some other questions were more curt, likely because he’s asked them all the time. These included:

Any chance of a new IP that takes place in the half-life/portal universe? “Yep”

Is Valve still working on any fully-fledged single player games? “Yes”

Wasn't there a movie (or a set of 2 movies) coming in that universe by Valve and JJ Abrams? “Yep. They’re coming.” (That project was announced back in 2013.)

It’s worth noting that Newell addressed the matter of Valve working on single-player games in 2015, years after the developer first hinted that 2011’s Portal 2 was possibly its final singe-player-focused game (despite that title having a major cooperative gameplay component).

For more answers from Newell, little of which will sate your appetite for Half-Life 3 knowledge, check out the full Reddit AMA or Gabe’s responses.