Aurelia's Downsizing

You place 4 chunks of ruby at the corners of a structure object or person in an attempt to reduce their size. An unwilling creature that is forced into the space for the spell's duration may at the end make a constitution saving throw. On a success, the creature is unaffected by the spell, on a failure, their size is reduced to tiny until dispelled. The structure or creature is reduced to a size that could fit into the palm of your hand, provided the structure is no more than 100ft on either side. Larger structures may require more gemstones, for instance anything more than 100ft on either side is double the gemstone cost and anything more than 200ft is double again and so forth. 

Once created, you may use an action to dispel the Downsizing, returning the object or creature to its original weight and density. Depending on the situation, this might involve creatures being shunted out of the way of the dispelled effect, and causing consequences and damage up to the DMs discretion.