Zombie game Days Gone features very specific Easter eggs related to Bend Studio's other big franchise, Syphon Filter. In an interview with Screen Rant, Bend confirmed that there is a very real connection between Days Gone and Syphon Filter, but it has yet to be fully seen what the extent of that connection is.
For those not familiar with Syphon Filter, it was a series of games that ran from the PS1 to PSP. The franchise followed Mission: Impossible-esque agents attempting to stop bioweapons and save the world from certain doom. There's plenty of clues within Days Gone that seem to imply that the zombie game was a secret sequel to the series and is a result of the other franchise's heroes failing to save the day.
Although fans may never see the full connection, due to a Days Gone sequel being rejected by Sony, fans can feel vindicated knowing their theories have weight. In an interview with Screen Rant, Days Gone's Lead Designer Ron Allen confirmed the Syphon Filter connection and doubled down on it when asked for clarification.
"I guess I can talk a little bit about that. You know that obviously, Syphon's really close to our studio's heart. We were the original developers, and we carried it all the way through until the end on the on the PSP. And, obviously, we're big fans of the Syphon Filter franchise in general. With the taser and things like that - I don't want to go too far into all of that, but - yes, there was a little bit of that crossover with Syphon Filter. What happened in all of that stuff is still to be determined."
It's possible that a hypothetical Days Gone 2 could explore this connection a bit further, even if it's not the core focus of the story. There's a larger world that Bend has built, and the studio confirmed it has a lot of lore and answers to many questions that fans may have written down in some sort of document. Whether or not any of this actually sees the light of day ever remains to be seen, but it's clear that Bend has a larger idea of where Syphon Filter fits into the world of Days Gone.
As of right now, it seems that Bend has been focused on delivering this new PC port of Days Gone and is reportedly working on a new IP. Fans are demanding a Days Gone sequel, but the ball is in Sony's court and it's unlikely that the company would scrap whatever Bend has been working on in favor of a sequel right now. Perhaps the platform holder will be more open to it if Bend proves itself with its next game, but for now, Days Gone will likely remain dormant for the foreseeable future.