If Red Dead Redemption's 13 million copies sold wasn't enough evidence that a sequel is likely to happen, then Take-Two CEO Strauss Zelnick's comments this week should hammer the point home: A sequel is most likely in the works. Speaking this week during the Cowen and Company analyst conference, Zelnick described the Red Dead brand as a "permanent" franchise that can sit alongside the likes of Grand Theft Auto or Borderlands.

Zelnick's comments came as part of a response to a question about why Take-Two takes a "selective" approach to releasing games rather than flooding the market with new games.

"It seems quite obvious that Red Dead is a permanent franchise" -- Take-Two CEO Strauss Zelnick

"The risk of just [releasing more games] is that you end up just bulking up your release schedule and that isn't really what consumers want. Consumers want better, not more," Zelnick said. "So our selective approach, which we've taken since '07 I think has paid off. Now, we have gotten more by taking that approach; we've launched one new successful franchise every year and I would like to keep doing that particularly because I talk about permanent franchises, but not everything is going to be a permanent franchise. Some of our great franchises eventually will lose their luster and some will hopefully be permanent."

"I pretty much know the ones that I can assure you are permanent. It's obvious that GTA is a permanent franchise as long as we keep delivering this incredible quality; it seems quite obvious that Red Dead is a permanent franchise, again with the same caveat, or Borderlands, for example, and NBA and others," Zelnick added. "But not everything is going to be a permanent franchise. We can do very well even if it's not. I would like to see us grow with a couple more great franchises in the next couple years and we're launching Evolve; we have very high hopes for that."

This is actually the second time Zelnick has referred to Red Dead Redemption as a "permanent" franchise, following comments from July 2013. Also during the presentation, Zelnick said Take-Two has an enviable track record of quality, though he did acknowledge that the company has made poor bets before--like 2011's Duke Nukem Forever.

"We have a really high hit ratio. It's probably not realistic to believe it could be much higher than it is. We've had precious few flops. And at least, of the few I can think of--and I can think of a few, sadly--at least one of them was just a misguided decision on my part, which was Duke Nukem," Zelnick said. "And a couple others are the natural success and failure of any entertainment company, except our hit ratio is much higher than anyone else's. So much as I'd love to say we make no mistakes, if you're not making any mistakes at all you're probably not trying hard enough. And the business does have inherent risk. And you do need to push the envelope. And if you're pushing the envelope, now and then you'll get it wrong."

Duke Nukem Forever was not adored by critics. But it was a top-selling title upon release in June 2011, and is considered by some to be the Chinese Democracy of video games, in that it's remarkable that it even exists. The game was announced in 1997 and was considered to be dead at multiple points before Gearbox Software scooped up the rights and finished it off.

"If you're not making any mistakes at all you're probably not trying hard enough" -- Zelnick

Finally, Zelnick was asked a question about the future of BioShock. He wouldn't give anything specific about where the series may be headed in the future, but agreed with the interviewer's suggestion that the BioShock series overall has not reached its commercial potential yet.

"We haven't given any color on how you should think about it yet except we do believe it's beloved; we think it's important [and] certainly something that we're focused on; something 2K Marin will be responsible for shepherding going forward. I don't want to say much else except to agree with you. I think there's a lot of upside in that franchise," Zelnick said. "It hasn't necessarily been realized yet. And the question for the future, assuming we decide to answer the question, would be 'How do you stay true to that creatively?'; 'How do you do something exciting?'; and 'How do you do expand the market?'. That would be the natural drill. We're starting from a good point on it. And certainly it's been a great piece of business for us; it's been a profitable piece of business."

The most recent entry in the BioShock series, last year's BioShock: Infinite, has shipped over 6 million copies to date. Developer Irrational Games dissolved earlier this year, and all development on the franchise in the future will be handled by 2K Marin.

Also during the investor conference this week, Zelnick defended microtransactions, saying, "We're in the business of delighting consumers. And when we design our virtual currency packs, we do it in a way that will make consumers happier, not sadder that they are engaged with our games. That is a different point of view than most of our peers in the business."