Your body and what you are wearing change in consistency, assuming a distorted aspect of yourself depending on wich form you choose to take: slimy, sponge or hollow.

Slimy form: you gain immunity to slashing damage and the prone condition, also your walking speed becomes 20 feet, you gain a climbing speed of 10 feet and you can spend 5 feet of movement to escape from nonmagical restraints or being grappled. You can also move through any space as narrow as 1 inch without squeezing.

Sponge form: you gain immunity to bludgeoning damage and the stunned and paralyzed condition, your weight is one eighth of your original weight, you fall at half the regular speed and float on liquids. Also you have disadvantage on Strenght checks and Strenght saving throws.

Hollow form: you gain immunity to piercing and poison damage and to the poisoned and exhausted condition, but you are vulnerable to bludgeoning damage.

During the duration of the spell, you can use an action to change your current form into another one of your choiche.