Roguish Trickster

You have trained your Roguish spells to hit your enemies' weak points and exploit openings.

Once per turn, you can deal an extra 2d6 damage to one creature you hit with a spell if you have advantage on the spell attack roll. The spell attack must use a spell you learn only through your Arcane Trickster subclass. Spells learned from other sources, such as feats or multiclassing, are unaffected. If the spell targets multiple times, you can only add sneak attack to one hit.

You don't need advantage on the spell attack roll if another enemy of the target is within 5 feet of it, that enemy isn't incapacitated, and you don't have disadvantage on the spell attack roll.

The amount of the extra damage increases as you gain levels in this class, as shown in the Sneak Attack column of the Rogue table.