Amulet of the Chameleon

A simple bronze pendant bearing the image of a chameleon in profile. When a creature first attunes to this amulet, they decide the appearance the amulet grants them - height, weight, coloration, hair color and length, sex, race, etc. While they can choose to appear as a different sex or race, this does not change their statistics or biological functions. If the user wishes to alter the appearance granted by the amulet, they must spend at least 10 minutes during a short or long rest re-attuning to the amulet. 

The illusion stands up to physical inspection. For example, if a thin creature uses the amulet to make themselves appear overweight or muscular, the added mass feels real to an outside observer. However, magical means of inspection, such as the Detect Magic spell, will reveal that the user's appearance is illusory.