The game was developed with RPG Maker and has a gameplay that's pretty similar to other games created with this tool. The major difference is that the fights are decided based on which option you choose from a pop-up window.
The combat system is incredibly simple. But instead of that being a problem, it's a success, letting you focus solely on the story and atmosphere of the game, which are the most important elements at play here.
During your adventure, you'll get different items, weapons, keys, notes, and healing items. And sooner or later, you'll need all of them to get out of tough situations, so it's a good idea to be careful with your inventory.
One Night: Full Circle is a horror adventure game with an excellent setting that will manage to give you a scare or two. Furthermore, the story is much better developed than the vast majority of games in this style.