Trying out this fun/competitive list, let me know what you think...

"its an almost pseudo warg attack from the two towers... just giving a bit more flavour to the list".

Warband 1
Sharku on warg with shield
5x Warg Riders with shield (2x with throwing spears)

Warband 2
Orc Shaman on warg
5x Warg Riders with shield (3x with throwing spears)
6x Orc trackers on wargs

Warband 3
Fimbul on warg
3 Hunter orcs

Warband 4
Narzug on warg

total: 500pts
models: 23
might: 10
break at 12; 25%= 6

Looks good, however the mordor warband is illegal as it wouldn't be able to take that many orc trackers. I took a crack at it and came up with:

---- Warband 1 6/12 (Mordor)
Mordor Orc Shaman with Warg;
2 Orc Tracker with Warg;
2 Warg Rider with Shield; Throwing spears;
2 Warg Rider with Shield;

---- Warband 2 6/12 (Isengard)
Sharku with Warg; Shield;
5 Warg Rider with Shield; Throwing spears;
1 Warg Rider with Shield; Throwing spears; Banner;

---- Warband 3 2/12 (Azog's Hunters)
Fimbul with Fell warg;
2 Hunter Orc with Fell warg;

---- Warband 4 2/12
Narzug with Fell warg;
2 Hunter Orc with Fell warg;

---- Warband 5 1/12 (Dark Denizens of Mirkwood)
1 Fell Warg

500pts 10might 21models

might be quite good. Alternatively you can drop some throwing spears and the fell warg and take another rider somewhere else.

forgot the trackers bow limit :P

thank you