Board Thread:Game Discussion/@comment-10101308-20130614044323/@comment-10660249-20130614064302

You pretty much just farm for cubes. You get 1 cube for finishing blow on a boss. You get free cubes per point awards during events. You also get extra cubes from "???" bosses. And the main goal is to never spend more than 1 cube killing any bosses.

Knowing all this, when you have 3 cubes charged up over time, if you use those 3 cubes to kill/snipe bosses you'll gain +3 cubes. And of course when you level up, you get your 3 regen cubes back, so you just continue doing this process.