Other mistake: Across the show Xena's past relationship with Ares is unclear. In "The Reckoning" (Season 1), Xena says to Ares that she used to wonder what he looked like - implying that they had never met face to face. Yet in "Succession" (Season 5), Xena asks Ares if this portal world is just to watch his new girlfriend fight and he responds, saying it is to watch his old girlfriend (Xena) fight. If they had been in a relationship, surely a: Xena and Ares would have met face to face and therefore b: Xena would know what Ares looked like.
Other mistake: Xena travels to the land of the Norse gods in 'The Rhinegold', 'The Ring', 'The Return of the Valkyrie.' Brunhilda says that Xena came from a distant land in the east, meaning that she travelled from Chin or Japa (most likely), not Greece. When would she have done this, and why is Borias not with her, etc.?
Other mistake: If Lyceus is killed 11 years ago (the second year Xena and Gabrielle travel together - 2x02) and Solan is born roughly 8 years ago (the same night Borias is killed), then in about two years, Lyceus is killed, Xena gets an army, Caesar betrays Xena, Xena meets Borias (and gets him to leave his son), they go to Chin and meet Lao Ma, Xena gets pregnant and meets the Amazons/Alti, Borias dies and Solan is born. No way does this all fit into a few years. And what happened after Solan was born?
Other mistake: As Xena and Gabrielle are walking along the river, the upper story of a modern A-frame house comes in and out of camera view in the upper-left corner.
Other mistake: When Callisto (in Xena's body) enters the cave hideout of Theodorus and his men, Theodorus assumes she's the real Xena. However, she walks in a Callisto-like way, indicating she isn't. Callisto's army never appears again either, not even after she becomes an immortal and a goddess. On her own in future episodes, Callisto still wears the same warlord outfit she wore when she led Theodorus and the army on village rampages.
The Debt (2) - S3-E7
Other mistake: At the end when it shows that Xena did kill the "green dragon", you can see his eyes move when the camera pans around his face to show the hair clip in his temple.
Other mistake: Ares says to Xena, "Are mortals so stupid as to believe that Dehok will actually bring them peace? They all get what they deserve. I really don't know why you continue to protect them." The Way this is phrased, "continue to protect them," seems to imply that Xena might not be mortal, yet in "Sacrifice II" he says, "You're the only mortal I know who can do that," which means that she is. Why was he implying earlier that she wasn't?
Other mistake: In Season 5 the majority of the gods are trying to kill Xena, Eve and Gabrielle. However, what happened to the gods that didn't intervene, like Demeter, Hestia or Cupid? We don't hear about them again, but they weren't killed, so what happened?
Other mistake: In Season 2 "Ten Little Warlords," Ares tells Xena that without a sitting God of War, peaceful people can't control their anger. Yet during the whole time in Season 6 that Ares is mortal, peaceful people can control their anger. Furthermore, in Season 6, Ares tells Xena that without the God of War the Goddess of Love becomes unbalanced. Yet in Season 2 there is no mention of this.