You’re right, and the rules (both 3.5 and 5) even explicitly state that after ten minutes the creature suffocates. I was hoping that the RAW was simply “holds enough air for a Medium creature to breathe for ten minutes” which I could try to argue was merely a statement about the inner volume of the bag.
Yes. It’s specifies there’s ten minutes of air. But the bag woodt need to be closed to not have air exchange.
You’re right, and the rules (both 3.5 and 5) even explicitly state that after ten minutes the creature suffocates. I was hoping that the RAW was simply “holds enough air for a Medium creature to breathe for ten minutes” which I could try to argue was merely a statement about the inner volume of the bag.