Enhance Gravity

You create a small gravitational anomaly within a specified area making the gravity exponentially greater than normal.

When a creature enters the affected area for the first time on a turn or starts its turn there, the creature must succeed on a Strength saving throw or will become prone until the spell ends.

A creature that is prone can use its action to make a Strength check against your spell save DC. On a success, it will no longer be prone.