Dong zizhong. The comparison between Dong Zizhong and Ren Gang is as follows:

1, Dong Zizhong became the youngest player in the World Chess Masters through online selection. At the age of twelve, he took another step towards his goal.

2. Ren Gang is a chess master in China, graduated from Peking University, and won the first prize in the 6th Weikai Cup Chess Championship in 2009.

To sum up, Dong Zizhong is better.