How to kill Black Dragons?

Then you won't have to finish them off later=) I think we're talking about that, weaken them first, then finish them off. By the way, this tactic works well against dragon kings, they're tough guys, I wouldn't let them into my army, unless I teleported them to the enemy camp, and if their troops are close to each other, then...:D it's going to be fun, who gets the roasted units)