In the downloads section, the intoruins_offline_carts.zip file contains the .p8.png cartridges. Into Ruins is a multi-cart game so both are required -- put them both in the same folder on your device and you should be able to launch intoruins.p8.png to run the game.
Note that if you are using an emulator rather than running pico-8 natively on your device there may be compatibility issues and I can't guarantee it will work. If you're running pico-8 natively and have wi-fi connectivity, you can also grab the game through Splore rather than downloading the offline carts.



















