Perhaps one of the most difficult things in Tichu and the one not discussed often is what to do in terms of threshold to call grand Tichu and what cards to pass when your team is behind on score.
There have been occasions when the team opposing team was 5 points away from winning that I have passed Dragon or Phoenix to partner after calling grand Tichu and it worked out with +400 double victory.
If you are in this situation where you are behind and your partner has called Grand Tichu, there’s debate even among the strongest players on what to pass.
i.e..you might not necessarily pass your highest card, which is ace, but K instead.
If my team is behind by 500+ points, I’m ready to call GT even with single A.
If the deficit is even higher, I’m willing to call grand with even less.
Sadly, some partners have disagreed with me because of this and even blocked me…but it is better to try to call grand Tichu and fail than to be afraid to call grand Tichu and lose anyway…especially if your team is way behind on score…