Chen (Relationships)

The Ninja
Chen was responsible for Zane's abduction and had Zane (as well as P.I.X.A.L.) stripped of his powers while holding him captive on Chen's Island for most of early rounds during The Tournament of Elements. Chen used the nindroid to lure his friends to the island and taking their powers. Chen manipulated the events surrounding the ninja, as he swayed their potential allies with promise of power and ultimately stripped all the ninja of their power. Of all the ninja, Chen despises Kai the most who feigned allying with him after Chen promised to reveal secrets about his missing parents, something that seemingly caused Kai to help in capturing Lloyd. After Kai not only revealed his deception, but turned Skylor against Chen and return the elemental powers to everyone. In spite of this, Chen achieved his goal and actively fought the ninja

The ninja watched Chen along with his cult being banished to the Cursed Realm after Garmadon's sacrifice, while pleased he can't do any wrong.

In Season 5, their new member Nya was ultimately responsible for killing him and sending him to the Departed Realm.

Pythor
Because of Chen and his followers turning themselves into Anacondrai, Pythor grew dislike at their audacity to masquerading as his proud race.

Pythor's disgust for them increased after he learned Chen caused the Serpentine War by lying to both sides. After they captured him, Pythor insulted them by calling them frauds, as they had him chased by a Swamp Rat to sweat out essence for them to maintain their form. Pythor was not pleased when a mocking Chen left him to his fate of nearly being devoured by said rat.

As revenge, Pythor tamed the rat and gave the ninja a spell that could defeat the impostors. He watched gleefully as they were banished to the Cursed Realm.

During "Day of the Departed," Pythor and Chen met again with neither being pleased to see the other and giving a tense acknowledgment. Despite that, they were united in wanting vengeance on the ninja.