Is there any way to improve visibility under ground? Is there a map in the game? How will you make this game increased publicity? Can you make your sword shoot fire? As for empty, I meant as far as questions.
There is a map already in the game, open your menu and select it (on the row below your inventory). There is also a shortcut (default key 'M'). It shows you where you have explored already. If you build a structure large enough, it will even be visible from this map.
At the moment, I think word-of-mouth will suffice in terms of increase the game's coverage. You can help with this if you want~ However, this is the pre-greenlight stage. Once the greenlight page has actually been created, I have other methods of showcasing the game idea around.
It's not quite fire, but there is a default power already in the game that can work with your equipped sword. If you are the fox or deer animal type, they have a innate power. Press alt fire (default key left ALT) to shoot it. It also works with an equipped axe or bow. Later, orbs will be implemented in the game which allow anyone to use powers while equipped. Fire is planned as one of the first orbs.