ADDING TO THE SPOILER WARNING. DON'T READ IF YOU HAVEN'T WATCHED TO THE END.
I think what Zang Hai did at the end was both risky and genius. He took his benefactor/enemy's teachings and basically turned them against him in two ways: (1) tell 9 truths and 1 lie; and the most important (2) give something away to get more back. I suspect that even when he handed over the fish to the emperor he was planning to expose his third enemy for all to see and drive the final confrontation. And then he did it again with the book at the end to draw him into the hallucination. I know some people think it was a bit of an anticlimactic ending but Zang Hai was not a martial artist. It was always going to be about wits and the audience picking up on the foreshadowing. I personally loved it.
I think what Zang Hai did at the end was both risky and genius. He took his benefactor/enemy's teachings and basically turned them against him in two ways: (1) tell 9 truths and 1 lie; and the most important (2) give something away to get more back. I suspect that even when he handed over the fish to the emperor he was planning to expose his third enemy for all to see and drive the final confrontation. And then he did it again with the book at the end to draw him into the hallucination. I know some people think it was a bit of an anticlimactic ending but Zang Hai was not a martial artist. It was always going to be about wits and the audience picking up on the foreshadowing. I personally loved it.