For those who have not completed Xenoblade Chronicles X, this page may contain spoilers regarding the plot. Discretion is advised.
Zo Zazhi is a Mission Exclusive Enemy fought as a Secondary Boss at level 39 in Oblivia during the normal mission A Dish Served Cold. Depending on the route taken, she is fought at either Jair Fortress or the Ant's Nest.
In A Dish Served Cold, as stated by her brother Zo Langra, Zo Zazhi left New Los Angeles to get revenge against the Ganglion assassin for the murder of their three brothers. Upon tracing her at the Ant's Nest in Oblivia, she demands Cross to head to the Jair Fortress and take down Siphon Qmoeva and Vanitas Seidr before talking to her. Upon their defeat, she is impressed by Cross' skills. Zo Zazhi refuses to return home and challenges them to a fight, she orders them to relay her message that Zo Langra does not need to worry about her. According to Zo Langra, she was taught by her former three brothers to only use the sword so that she may live, they also taught her not to kill. Zo Zazhi calls her brother to inform him that she tracked the assassin to his base at the Jair Fortress. She becomes disgusted when Zo Langra suggests bringing a force of humans to assist her, she insists that vengeance should be taken by the House of Zo. She abruptly ends the call. Zo Langra requests Cross to remind her of their brothers' wishes by bringing the three swords used by the Zo brothers. Upon bringing the swords to Zo Zazhi, she continues to act stubborn and gets into a battle with Cross. After her defeat, she realizes that she is not strong enough and thus returns to New Los Angeles. She vows to become stronger so that she can get her revenge one day.