Fade Away

Source: Xanathar's Guide to Everything p. 74

Prerequisite: Gnome

Your people are clever, with a knack for illusion magic. You have learned a magical trick for fading away when you suffer harm. You gain the following benefits:

• Increase your Dexterity or Intelligence by 1, to a maximum of 20.
• Immediately after you take damage, you can use a reaction to magically become invisible until the end of your next turn or until you attack, deal damage, or force someone to make a saving throw. Once you use this ability, you can't do so again until you finish a short or long rest.