For the duration, no sound can be created within or pass through a 20-foot-radius sphere centered on a point you choose within range. Any creature or object entirely inside the sphere is immune to thunder damage, and creatures are deafened while entirely inside it. Casting a spell that includes a verbal component is impossible there.
How does this work in practice?
Say an enemy wizard is 40 ft away and casts a 60ft range spell that requires Verbal (V).
- If I'm standing inside a sphere of silence can his spell affect me?
- If I'm not in the sphere of silence but the wizard is can the spell affect me?
- If the Wizard is in the sphere of silence, are they immediately aware they're in the sphere (and will thus use their turn for non-verbal things) or are they oblivious to this and would have to first try to cast a V-Spell and then question why it didn't work?
- If we're in something like a 10 ft wide hallway that's 200 ft long. The Wizard is at the far end but already starts shooting spells at us. Would placing the Sphere of Silence at its maximum 120 ft prevent any of the Wizards spells from passing through it since there's nowhere else for the sound to travel?
- How will I even know if the Wizard I'm facing is using a Verbal spell if the DM doesn't always act it out to that level of detail?