Wailing Anchor

You invoke a spiritual anchor on to a target you can see within 100ft. The target must make a strength saving throw or become anchored. On a success, the creature loses only 10ft of movement while affected by the spell. While anchored, the creature's speed is halved, and it cannot willingly move away more that 10ft from the anchor without a successful Strength (athletic check).
Flying creatures are immediately grounded, taking the respective falling damage, and a swimming target falls to the bottom of the body of water they are in a at a rate of 15ft per turn.