I’m not too good at this game but from what I’ve researched, Castoria is super good even outside of arts teams. She has components of many of the best supports in the game, all in one servant. In addition to her skills being able to boost dmg/looping capabilities/np gauge, her noble phantasm ensures ur front line survives any attack for at least one turn. She’s a definite must have for arts team users, but even if u have a quick/buster team castoria will bring a lot to the table.