Black Hole is one of Natz limit breaks in EBF 3. It is the most devastating limit break, cause it is the skill that deals out the most damage at once. At it´s max level, it´s skill power is 500, and the description explains pretty good it´s own power:
-"Element: 100% Dark
Limit Break! Deals extreme dark damage to all foes and players. Chance of instantly killing foes and players."
Epic Battle Fantasy 4
Black Hole will return in EBF4. It will be largely the same, however this time around it is one of Lance's limit breaks.