Skeletal Cage Confinement

skeletal cage confinement: The user throws out multiple ribs around the enemy, and they start to grow to close around into a cage around them leaving them stuck and unable to move. The cage can withstand 150 points of damage before breaking. Each round the wall is restored up to half of its max HP and closes in by 20ft. When the wall closes in targets inside that were near the wall are pushed towards the center and begin taking damage when the walls can no longer close in. Rank: B. Style: Kekkei genkai. Chakra cost: 40 per round. Range: 80ft cube centered within 160ft of the user. Save: 14, pow for half damage. Damage: 3d12 force per round. Focus: Yes. Requirements: None. Enhancement: +1 damage die. minor Action