Tien Tao Lien (天道連, ティエンタオレェン, Mandarin pinyin: Tiandaolian) is a criminal gang or mafia from Taiwan in Persona 2: Eternal Punishment.
The organization is led by Yung Pao (云豹) whose little brother has been held hostage by Tatsuzou Sudou, the leader of New World Order. For this reason Yung Pao and his gang has traveled to Sumaru City, Japan to do Sudou's bidding. Maya Amano, while guided by Baofu, runs into the gang when they are trying to bring Tatsuzou's mentally unstable son Tatsuya Sudou into custody who effortlessly wipes out the gangsters with his demons. Using the telecommunication records received from the police, which is already under the influence of NWO, Tien Tao Lien also abducts users of the Joker Curse and brings them to Takahisa Kandori's laboratory for experiment on extracting the Joker Persona from the users. They have restructured the innermost hall of Club Zodiac as an illegal casino for earning and imprisoning the abductees before transferring them away, using drugs to suppress the ability of the Joker Persona temporarily.
When confronted by Baofu in the casino, Yung Pao sarcastically complains to Katsuya Suou the unfairness that Baofu killed 25 of his men in Taiwan, comparing his single Japanese victim (most likely referring to Miki Asai, Baofu's deceased partner). Then Yung Pao liberates Noriko Katayama whose efficacy of Joker suppression drug has just faded to buy him time to flee from the query.
After the extraction of Joker persona has been perfected, Tien Tao Lien has no more use to the order, so Sudou lies to Yung Pao that he will liberate his little brother in the Abandoned Factory. This in fact is a trap set up to annihilate the gang as well as testing the newly developed X robot for collection of combat data. Baofu corners Yung Pao, albeit knowing that he is also Sudou's target, but before shooting Yung Pao in the head he is halted by Katsuya, who reveals the grudge between the two and Baofu's true identity as the former public prosecutor of the Department of Justice. While the two argue, Yung Pao is critically wounded by the X-1 robot. Before he dies, he informs Baofu about the location of Sudou's maritime headquarter, Nichirinmaru.
After this incident, Katsuya further explains that five years ago Sudou ordered the Department of Justice to set up a trap to kill Baofu in an investigation to Taiwan about the money laundering between Tien Tao Lien and the Minister of Justice. Yung Pao killed Baofu's partner investigator, Miki, but Baofu survived the assassination due to awakening of his Persona, Odysseus.
Tien Tao Lien is based on the real Taiwanese gang(天道盟) which has been active since 1985. While Baofu mentions that Tien Tao Lien is being hunted by Taiwan Government, in the Japanese version, the operation specifically refers to the "First Purification Case" (一清專案) with unconstitutional enforcement. In reality, the operation was being carried out in 1984 and inadvertently caused the rise of Tiandaomeng.