The Deity Catastrophedragon is an ultimate dragon.
But with high cost so many people don't want to add them in their deck.
As for me, catastrophedragon may high cost. But what about combination of spirit illusion, nature force or another. That can bring it to the highest level at BP 20000 very easily.
You use catastrophedragon in a combo with anything that can rise the level but not waste turns and cores. If you face a purple card battler, be sure to summon it with more than one core. If you have spirit illusion or nature forces, feel free to summon it.
Strategies and game play:
This spirit is scary with its level 3 effect. You can see example in Battle Spirits Shounen Toppa Bashin ep 50. Even the high BP spirits like hercules-geo or the risedragon balmung will become a prey and then this spirit will refresh. Another example exists in shounen gekiha dan ep 8 . In battle with suzuri, catastrophedragon eliminate all four spirits.
Combos with other cards:
Cards that can rise the level of this spirit quickly are the best.
Ways to counteract it:
Purple deck is good. With core-takeout abilities they can take it down . For example, If your opponent summon catastrophedragon at level one and wait for the next turn to level it up. You better use the sevenshogun desperado or poison shoot against it.
-High BP at BP 20000.
-level 3 ability that can keep it refresh or force your opponent to destroy their strong spirits. Together with clash.
-high cost . spirit with a cost of ten is hard to summon.
-can be drag out easily by poison shoot