Delthorns Unrelenting swamp

You alter the ground within a 50 feet range and turn the affected ground into a Muddy Swamp, the area affected is a 30 foot radius. Each target must succeed on a strength saving throw or be unable to move, if they succeed then the creature can move but only at half speed. 

An affected target's can't use reactions, on its turn, but can still use actions and bonus action. If a creature ends their turn in the Swamp they take 3d4 poison damage. And as a Bonus action on each turn you can summon muddy tentacles with a 15 foot range to attack a creature using your spell modifier. On a hit the creature takes 2d10 bludgeoning damage and 3d4 poison damage.