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.
Xena: Warrior Princess (1995)
1 other mistake in season 6 - chronological order
Revealing mistake: When Xena 'dies', her pulse is checked, and they can't find one, yet you can see her pulse in her neck. (00:30:30)
Trivia: Karl Urban, who plays Cupid in this episode, also plays Caesar in many episodes.