Light Soul
You can obtain Good Karma when you defeat a Evil Karma player only. It is harder to get since you can't get Good Karma from killing Neutral players. Light Souls and Chi are the main currencies you can use in the Light Shop The Light Shop has the best training area called the Zen Master's Blade. It multiplies your Ninjitsu by x25 (More with light karma boosts) and multiplies Coins by x40 (If you have auto-sell and gives more multiplier with light karma boosts) and Multipliers apply to this as well. Go to Light Karma Shop to learn more about the skills you can learn there.
Do not be confused with Good Karma. It happens.