I know the traffic here is light at best these days but I wanted to tap judges experience. I had a player ask if casting with subtlety or using the meta magic power subtle spell defeats Counterspelling. Obviously you can't cast counter spell against a spell you were never aware was cast. On the other hand even a gnomish sorcerer (for example) conceals that *he* cast a fireball, you can't make the globe of kaboom disappear. Can it be counter spelled? Or is it already too late when a second sorcerer feels the heat of the explosion?

https://www.dndbeyond.com/sources/sac/s ... compendium


Apparently this is also covered by Xanathar’s Guide to Everything on page 85 (I don't have the book itself).