Is it possible to cast spells on places that can be seen through a familiar?
A wizard is inside a room and their familiar is outside of it. An enemy is also outside, in front of the familiar. Would the mage be able to cast, for example, frostbite on that target?
You cause numbing frost to form on one creature that you can see within range [...]
on that target? I'm aware looking through your familiar is an action, but let's assume the wizard has multiclassed into a fighter and has Action Surge.