This is a standard playing card variation of the trading card game that we've all come to know and love. A deck of playing cards for each player is all that is needed to play, which makes it cheap and portable. It's also open source, so all of the rules are customizable. Take a look at the links below and let me know what you all think.
Tutorial: https://www.youtube.com/watch?v=abnPjbKF1a0
Reference Guide (Updated): https://docs.google.com/document/d/15UqGKYXvYdiRPyq312GFmeFXY4vhKijkm3jB0TRqcyY/edit?usp=sharing