(Around 18 minutes) when Perdicas' blue arrow hits the Greek archer there is another blue arrow in his back which was not there before.
(Around 41 minutes) Gabrielle is holding her staff near the top as she climbs up the slope but when she turns round to look at the horse her hand is lower down.
Xena fights in the Trojan War in this episode. But previous Xenaverse episodes referred to the Trojan War as having happened in the past.
At around 18:00, one of the guards on the wall yells, "ARCHERS!" and is hit with a flaming arrow and proceeds to fall over the "stone" wall. As he falls, you can see the "stone" wall wobble.
Right after the Trojan Horse is opened, there is a large crane shot of Deiphobus on the castle, where a crew member is obviously crouching down behind him to remain out of sight.