This mod adds 67 in minecraft. Try "/67" or find a structure! <iframe width="560" height="315" src="https://www.youtube-nocookie.com/embed/0zyjCDf60LI" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe> Up there are a guide how to do an altar that spawn something.
