The Secret Murakumo from BT09

Hi everyone ! Earlier, in the past week, we were talking about the new BT09 cards, and the famous Secret Murakumo that was going to get released in the same set, but with an unknown effect. Here it is !

Bonjour à tous ! Plus tôt, dans la semaine passée, nous parlions des nouvelles cartes BT09, dont la fameuse Unit Murakumo classée Secret qui allait sortir dans la même extension mais dont l'effet était inconnu. Le voici !

BT09/009 RR
むげんのかざはな シラユキ Phantasmagoric Snowy Wind, Shirayuki
Grade 3/Murakumo - Ghost/11000 Power/No Shield
Auto: [VC] Limit Break 4 (This ability is active if you have four or more damage):[Counterblast 1, Choose a card named "Phantasmagoric Snowy Wind, Shirayuki" from your hand and discard it] At the beginning of the guard step in which this unit gets attacked, you may pay the cost. If you do, select up to one attacking unit, and that unit gains -20000 Power during this battle.
Cont: [VC/RC] Leader (If there is a unit on the field that does not share the same clan as this unit, this unit cannot attack)