theres a list on smilebasics website, or you could just start typeing on a new line in edit mode, chose one of the options that comes up on the bottum scren and then click the ? button on the top right
a good way to balance is to make a "power curve". On a graph plot points of attack power on the y axis and cost on the x axis. you should generally see a line through it all. if anything is to high above the line, raise the cost or lower the amount of damage it does