Every situation and choice in this game has been defined by other players, and all this is stored on the Ethereum mainnet.
Play the game here: https://anallergytoanalogy.github.io/blockchain-adventure/
You'll be presented with situations, for each situation you'll be given one or more choices with what you want to do in that situation, and you just need to click on whichever option seems like a good idea.
If you reach a point in the story that nobody has written yet, you'll be given the opportunity to write your own situation. You can add as many choices as you want to the situation.
If you want to create a game-over situation, then just don't add any choices.
Contract Address: 0x77b4acc38da51a0e77c77355cfd28c1a6619f6ba
Also wrote an article explaining some of the contract code.