I found no info at all for this so if ur like me and very tentative about diving in with no help then ur in the right place.
sry all, no pics, but its easy enough and only requires 140 troops...
50 attack archers, 50 attack cav, 40 heavy archers, 2 x marshals (I also took 100 attack infantry but I don't think these ever came into play)
when u arrive there are 2 camps to ur east. hit them both (not at same the time) with 25 archers + 25 cav (+50 inf if u took them)
attack with cav 1st (u'll be prompted for this). keep ur eye on the fight and when enemy ranged are almost dead, click ur army and select ur ranged.
(the enemy will start fighting with inf. ur ranged is better for this and they will swap places with ur cav as soon as they can (like bringing on a sub in footie))... time to head south!
u now have a quest to block. this is what ur heavy troops are for. bb could not have made this any easier as it isn't even necessary to block here so sit back and bask in ur own confidence. move to the southern border. There's some rocks in the centre, put ur blocking gen to the west of these and ur attacking gen to the east. load ur blocking gen up with 40 heavy archers. load ur attacking gen up with all archers and cav u have left (and top up with inf if u took some).
send ur blocking gen into the little camp. give it a second and send ur attacking gen to the big camp, using cav 1st, don't forget to change to archers during the fight to save a few troops.
That's it, job done and I even managed to get a football reference in there (apologies to chickenhedz)
I hope u now have an idea of how pvp works and can try more, hf
P.S. if any1 successfully follows this guide without taking infantry along, then please let me know and I can make ammendments, ty.