When you cast mire, you create a 10-foot-diameter pit of quicksand, sticky mud, or a similar dangerous natural hazard suited to the region. A creature that's in the area when the spell is cast or that enters the affected area must make a successful Strength saving throw or sink up to its waist and be restrained by the mire. From that point on, the mire acts exactly as quicksand (see the GM's rules), but the DC for Strength checks to escape from the quicksand is your spell save DC. A character outside the mire trying to pull another creature free receives a +5 bonus on their Strength check against that DC.