You create a chaotic cloud of butterflies in a 20-foot-radius sphere centered on a point you choose within range. The area is heavily obscured, and resting smoke or fog in the area is dispersed.   Creatures of your choice in the area when you cast this spell ignore the following effects. For the duration, the affected area is difficult terrain. When a creature attempts to leave the spell’s area, it must make a Strength saving throw. On a failed save, it is pulled back to an unoccupied space closest to the center of the sphere.