Doom creators John Romero and Adrian Carmack canceled their days-old Kickstarter campaign for their new first-person shooter, Blackroom, saying they're going to focus on developing a playable demo.

In an update posted to their crowdfunding campaign, Romero and Carmack say the team at Night Work Games is working on a demo "which demonstrates the kind of gameplay, look and innovative, cool features that make Blackroom truly unique — the things we've waited years to put into an FPS and which make us incredibly excited about this game."

The developers say they're "pressing pause" on their fundraiser to complete the demo; work on the demo would take longer than the time remaining on their Kickstarter, they explain, and they'll relaunch the campaign at a later date. The developers cite player feedback in their decision to pause their campaign.

Night Work Games was seeking $700,000 to fund development of Blackroom. The developer had raised $131,052 from backers since the Blackroom Kickstarter campaign kicked off on Monday.

Romero and Carmack announced their new game earlier this week, describing Blackroom as a "visceral, action-packed FPS set in a holographic simulation gone rogue."