The gravity in a 10 foot radius sphere centered on a point you can see within range increases for a moment. Each creature in the sphere on the turn when you cast this spell must make a Constitution saving throw. On a failed save, a creature takes 2*D8 force damage, and its speed is halved until the end of its next turn. On a successful save, a creature takes half as much damage and suffers no reduction to its speed.
Until the start of your next turn, any object that is not being worn or carried in the sphere requires a successful Strength check against your Spell DC to pick it up.
This is a Dunamancy spell and it should be discussed beforehand with your DM.