Compression

The caster opens their hand and closes it suddenly. As the hand is closed, the target is compressed and must roll a constitution saving throw. If they fail, they take 6D8+6 force damage. If they succeed, they take half damage, but are still compressed. While compressed, the affected creature has disadvantage on strength, constitution and dexterity saving throws for 1 round. When 1 round has passed, the target elastically springs back to normal as if nothing happened. Whilst a creature is compressed, their size becomes 1 ft. and they can reach small places that they could not normally.