MurkyTime is a system agnostic, turn based, time tracking focused procedure for TTRPGs. You can plug it into most games if you want time to be a factor and to drive players to making meaningful choices. Great for dungeon/hex crawls, but other stuff too!
It's an amalgamation of ideas from games I enjoy, and some of my own. I'm using this system at my table and it works a treat.... [click here for more]