Can a Magus spend more than one point on his/her black blade to give it more than just one type of energy damage? Can you spend 2 points to give it fire AND cold? Or does one replace the other? I had someone curse at me saying it doesnt say anything about one replacing the other but I thought the general rule about energy enhancements was that you only get one type. And if you tried to do another it would replace the previous.
Or at least thats how energy resistance works. If I cast resistance to fire and then resistance to cold, the cold replaces the fire.