What is better in a 1 unit army - 1 red or black dragon

[dashcunning]

Originally Posted by N3MES1S

but i tested on the battlefield and i cant kill a red dragon with a black one, he dies first..even when black has more def and more hit points...

You are either exceedingly unlucky, doing something wrong, or forgetting/omitting some vital information. All else being equal, a black's normal attack does ~30 to a red and a red's does ~18 to a black. A black's special does ~30 to a red and a red's does ~20 to a black. Both specials have the same recharge time and both can easily be used whenever available to attack the other. A black has 130 more health than a red. Your claim doesn't add up.