Vestige of the Land's Soul

You call upon the power of the land to rise up against your foes. You summon tendrils to drain the life from your enemies while invigorating yourself. Make a ranged spell attack against one creature that you can see in range. The target takes 5d12 necrotic damage and is grappled. The target can attempt to free themselves from the slow as an action with an Athletics or Acrobatics check with a DC equal to your spell DC. 

While the target is grappled, it takes 1d12 necrotic damage at the start of its turn and you regain hit points equal to the damage roll.