The Awakening - cool RPG adventure game. Energy is good because it increases your damage and armor, and also gives a little bit of gold bonus - the more you have. It's always filled in the beginning of a battle. Limit Breaks are powerful attacks, and the bar for it gets bigger when doing pretty much anything, but mostly for getting hit. To use Diamond Bolt, click on your enemy, and press X to cancel the spell. In the inventory if you hold over the 'help' button you can read some more.