Board Game Arena

I thought about it again and stay with what I said about why a comm is needed. If the first player comms the 9g and then the second player holds back the 5 because they think I have the 7 or 8 and then I rocket the trick as the third player thinking that the forth player has the 5g.. I know the prob...

It depends on who starts. If its your turn and you start with the 2, then you don't need to comm the 8. (Whoever has the 5g has to comm if its a single g)
But if someone else starts and you don't comm the 8 then I go by the principle of "no comm no prob" and assume you rocket