Source: Mordenkainen's Tome of Foes

Prerequisite: Gnome (Deep Gnome)

You have inherited the innate spellcasting ability of your ancestors. This ability allows you to cast Nondetection on yourself at will, without needing a material component.

You can also cast each of the following spells once with this ability: Blindness/Deafness, Blur, and Disguise Self. You regain the ability to cast these spells when you finish a long rest. Intelligence is your spellcasting ability for these spells