The custom_heroes_river_of_blood_by_malerkoh_.zip file you have requested: Maps / Multiplayer / Custom Heroes River of Blood - 70.8kb is not available. Perhaps try browsing all files for the game Battle for Middle-earth II and upload any files you want to share or are missing. This is the only information we could locate:
This map puts you and up to 6 other players against the forces of evil. You have to defend the city of Lothlorien with your custom heroes, all there is between the enemy and Lothlorien is a bridge where, and I quote from 300, "numbers count for nothing". It's advisable to have archers and mages that deal AoE damage to kill a load bunch of units, the archers will help kill the Fellbeasts towards the end.