No. If you're having trouble make use of the Javelin Ana gives you. When Xol goes under, run back to the underpass where you first enter. Shoot ads from there, when the screen becomes green, stay under the the underpass. He will charge through the map, but he never goes through that area. He goes near it, thats about it. Nokris is harder than Xol, lets just say that. If you can beat Nokris then you'll beat Xol. Only thing you have to watch out for his is Ground attack, where the floor turns purple.