[foota]

You can of course play however you want (and I certainly think this is clever), but imo this is likely against the spirit, and perhaps letter, of the rules.

The rule on giving clues is:

"If you are the spymaster, you are trying to think of a one-word clue that relates to some of the words your team is trying to guess. When you think you have a good clue, you say it. You also say one number, which tells your teammates how many codenames are related to your clue." (emphasis mine).

The rule states that the number should be the number of words related to the clue. There is later provisions allowing you to use zero and infinity, but outside of these carve-outs (and imo the "allowed" language is telling here, since it implies any other number not equal to the number of words is not allowed) I don't think this is legal.

[pama]

We always allow any number when we play, because part of the thinking is we cannot be sure what the spy master has in mind. Of course, the number is related to the clue but possibly also to the game history up to that point. The teammates and opponents might interpret it wrong, and that’s OK. Infinity is typically used when there is enough info in principle to finish the game and a high risk if you dont; zero is super rare. We do tend to have very aggressive bids with tenuous connections, and 4 or 5 for a clue word are used in most games. Often, they don’t all work out in a single round, but on some lucky boards or in spousal teams, they occasionally work well.

[hunter2_]

You have a valid point, to which I'll concede. The rule book gives an example (spanning pages 4-5) where a guesser uses prior clues to select a card while the count is still within the number stated by the spymaster, but I suppose an allowance for guessers to deviate in this way does not also imply that spymasters may deviate in this way. Mea culpa!

Taking this a step further, given that it's well-known that a clue is deemed invalid when it pertains to cards in certain non-definitional ways (sounds-like, number of letters, etc.), it seems extremely reasonable to call a clue followed by N invalid if it doesn't pertain to N cards in a definitional way.