Ruinous Explorations

Worlds Without Number is Kevin Crawford's fantasy OSR game of sandbox adventure. The rules in this supplement add solo play to that game. It uses a simple set of rules to push decisions out to dice rolls. These answer yes-no style questions, control NPCs, and events outside your character's control.
There is an icon-driven oracle for creating concepts. These are used to answer questions that cannot be answered yes or no, and for creating features of your adventures.
I also the technique of custom oracles. These are a simple d6 table with four entries, two more common, and two less common. You will create these on-the-fly, as you play. They add a level of detail that is perfectly customized to your style of play. There are plenty of examples of creating these instant, bespoke tables.