with a brand of castigation, is a rogue is marked, can they just not sneak attack the person who marked them? Since they always know where they are Sneak Attack comes whenever they have advantage (the defender is harried, the rogue has other benefits, etc), so not necessarily. I personally would say it might greatly reduce the effectiveness of them using the Hide action/ambushing.
— Matthew Mercer (@matthewmercer) September 7, 2021
Brand of Castigation: Can rogue sneak attack the person who marked them?
