Recently there were questions [1, 2] discussing the possibility of having a prisoner tag. The main criticism about it is that the same question could be asked for a group of islanders, lab rats, etc.. What these questions have in common is that multiple individuals have to agree on a strategy to reach a common target. Hence, I propose the tag cooperation-game. An alternative name for this category could be limited-communication (with a slightly different meaning).
The tag description would be something like
A puzzle about finding a strategy involving several individuals cooperating to achieve a common aim. Examples are prisoners trying to avoid an execution, a group of people trying to guess the colors of their hats, or a magician and his assistants.
The tag would be a bit more specific than just strategy because strategy also tags questions where a single person has all the information and optimizes the strategy on this.
On the other hand, the cooperation-game tag would encorporate all hat-guessing questions and a part of magic questions, like this one.
The use of such a tag is of course an easy search for people interested in "$A$ knows that $B$ knows that $C$ knows..." questions. But besides from that I can also imagine that for example a RPG gamemaster will have fun making his group solve one of these puzzles "live".