I’ve ditched the first idea because after some  more though into it found out it had some severe flaws. I’ve came up with a new one instead that seems more interesting. The main idea I want to explore is that you’re SAFE beneath the surface. I will do a roguelike game with burrowing as safeness mechanic against enemies. Burrowing saves you but it drains air every turn. So you can burrow for few turns. But burrowing at the right time can cause enemies to clash and annihilate each other if they are the same, or one can eat the other base on some rules.

Here are some shots of what I’ve managed to do so far (I have a grid and I can move the player :D)