Prerequisite: Gnome (Deep Gnome)
You already have inherited a innate spellcasting ability of your ancestors.
Al though this ability can allow you to cast the Nondetection on yourself at will, but it is without needing the material component. Even you are also capable of cast each of the different following spells once with this ability: Blindness/Deafness, Blur, and Disguise Self. You could regain some ability to cast these spells whenever you finish the long rest. The intelligence is your spellcasting ability for all these spells.
You also have to read: skulker dnd 5e feat.