Mercy Thompson Series #1: Moon Called

• the spell that keeps them appearing human

Mercy Thompson Series #2: Blood Bound

• the fae change their appearance by magic–glamour, they call it…not entirely sure that the fae can see through each other's glamour¹²³

Mercy Thompson Series #3: Iron Kissed

• glamour works best for sight and touch, very good for taste and hearing, but not as well for scent¹⁵
• if glamour has a weakness it is scent²⁸
• the only thing all fae have in common is glamour, the ability to change their appearance; the illusion is so good that it affects not only human senses, but physical reality¹³
• it's not shapeshifting, but it's as close as makes no never mind¹³

Mercy Thompson Series #5: Silver Borne

• with enough glamour, a fae can take on the appearance of any living thing, but something inanimate is harder⁸⁸
• their true faces are concealed behind other forms – and designed to blend in with the human race and hide what they truly are¹²⁴

Alpha & Omega Series #2: Hunting Ground

• few of the fae are beautiful with their glamour on; beauty doesn't blend in very well. the fae, like werewolves, spent a long time learning to hide in plain site⁴⁹