Dr. Flumph's Zero Gravity Field

In a 100-foot-radius, 150-foot-high cylinder centered on a point within range, there is no gravity. All creatures that aren’t somehow anchored to the ground in the cylinder start floating around within the cylinder, moving at a rate of 5ft per round in whatever direction they propelled themselves when they were walking or running on the ground. A creature can make a Dexterity (Acrobatics) check to try and grab hold of an object floating around in the area or an anchored object. Any creature not within 5 ft. of the ground and not anchored to a stationary object in the area when the spell’s duration ends or concentration is broken plummets to the ground and takes appropriate fall damage. If an object is floating and the spell ends, creatures underneath it must make a Dexterity saving throw or receive appropriate fall damage from the object.

While the spell is in effect, any creature that is using effects such as Spider Climb or has a climbing speed and is capable of moving up walls and ceilings has its climbing and walking speed halved (rounded down). A creature with flying speed can fly in the area, but its flying speed is halved (rounded down), and if it moves toward something anchored on its turn and is its current speed or less away from the object once it ends its movement, it must make a Dexterity (Acrobatics) check at the beginning of its next turn against your spell save to make sure it doesn’t keep floating at its speed into the solid object. On a success, it takes its turn as normal. On a failure, it takes 1d6 bludgeoning damage for each 5 ft. of its current flying speed, crashes into the object, is Stunned for 1 round, and loses its turn.

A creature that has none of the benefits in the above paragraph or that wishes to do so can make a Strength (Athletics) check or Dexterity (Acrobatics) check to try and propel itself by pushing itself off of another object. If the creature succeeds, it propels itself 5 feet for each 1 by which it succeeded the check in the direction of its choice; if the object used to propel the creature isn’t stationary, it moves the same speed in the opposite direction. Like flying creatures, they must make an Dexterity (Acrobatics) check at the beginning of their next turn if they end their turn and an object within half the speed they moved and is in their path, or else take 1d6 damage per 5 feet of distance moved last turn on a failure.