My Take
I think it can be an effective teaching tool for those with no coding experience at all. It is very simple, and that being said relatively limited. For beginners, it appears to be really fun and engaging, however, it also seems like a game that could get boring for its simplicity and easiness once students become more experienced coders. I like that it promotes creativity as students can design their own characters through drawing, coloring, etc. I also like the simplicity of the design of how you drag the pieces down to add them to the code. Watching the code in action would be fun for the students as they get to see their creations combined with their codes tell a story. It is great for getting those interested in coding because of the creative expression. However, it is not something that I think students would remain engaged with after playing it for a while due to its simplicity. It is definitely something to catch students' attention and convince them to try, which for learning code is a great start!
How I Use It
I would use this as entire class activity. The purpose is to have the ability to tell a story, and watch it unfold. Having the entire class participate in creating that story and seeing it in action, I believe would get students engaged and want to try it on their own.