For gaming purists, there is only one true art to master -- RPS. From Advanced RPS:

"“Mystical” Schools

Finally, it bears mentioning that there are also “Mystical Schools” of RPS. These instruct students to select their throw based on some inner force, higher power, or telepathic premonition. Such approaches vary so widely among themselves and results are so mixed (or mixed-up!) that there is no point in trying to catalogue or categorize them. Nevertheless, the well-trained RPS player will be aware that these schools exist and know their basic tenets."