Arcane Trickster FAQ
How does Arcane Trickster interact with Sneak Attack?
Arcane Trickster does not replace Sneak Attack with spell damage. Magic is strongest when it creates a better Sneak Attack turn: invisibility, illusions, control or Versatile Trickster can help produce advantage or safer positioning. Magical Ambush works in the opposite direction, using Rogue stealth to make saving-throw spells harder to resist.
The base Sneak Attack rule still applies
Sneak Attack still follows the normal once-per-turn Rogue rule and requires a qualifying finesse or ranged weapon attack. Arcane Trickster adds magical ways to create favorable conditions, but a normal spell attack does not become Sneak Attack simply because the Rogue cast it.
Subclass interaction
Arcane Trickster does not replace Sneak Attack with spell damage. Magic is strongest when it creates a better Sneak Attack turn: invisibility, illusions, control or Versatile Trickster can help produce advantage or safer positioning. Magical Ambush works in the opposite direction, using Rogue stealth to make saving-throw spells harder to resist.
Reaction attacks can still matter
Off-turn weapon attacks can still matter because Sneak Attack is once per turn, not once per round. If a reaction attack qualifies on another creature's turn, it can carry Sneak Attack even if you already used Sneak Attack on your own turn.
Do not double-count subclass damage
Spell damage and Sneak Attack are separate unless a spell or feature explicitly includes a weapon attack that qualifies. Do not add Sneak Attack to a saving-throw spell or ordinary spell attack merely because the Arcane Trickster knows it.