Project Adder is an open-sourced 2D zombie shooting sandbox game, blending run & gun mechanics with rogue-lite elements. Open Sourced under GNU GPL V3.
Fullscreen support is poorly implemented atm, and the game automatically fullscreens when the menu loads. Instead there should be a menu button to toggle fullscreen. Additionally fullscreen is not working in NW.js exports, and needs to be controlled with that object when on that platform. For an example of this working correctly, see https://github.com/ReflextionsDev/RTR