I love the concept of tracing out a symbol to perform an action which the strength of is tied to how well you traced it, but I do wish there were a few more options to choose from. I felt like I just had to trace the shield on either side like once a minute and then spend the rest of the time tracing the swords to essentially live forever. Some sort of increasing difficulty would be nice too, but maybe I just didn't get to that in the few minutes I played.
Overall, this was a very interesting and unique mechanic that I could see a full game being built around.