Swords of the Iron Legion (1988)

From the back cover:

Ravening armies sweep across the land! Vast hordes of foul monsters lay siege to mighty cities! Tremendous battles are fought to decide the fate of entire lands - and you are in command!

Swords of the Iron Legion is an anthology of adventures set in the FORGOTTEN REALMS campaign setting for large-scale battle using the BATTLESYSTEM rules for mass combat. The adventures, written by a group of talented designers, range from simple skirmishes to all-out wars! Flying creatures, war machines, fortifications, and plenty of other twists ensure that each scenario is more than a simple bash-'em-up. Some adventures also include role-playing opportunities for characters, who get a chance to perform individual heroics to lead their armies to victory!

These adventures are suitable for one-time play, or they can be inserted with ease into an existing campaign. Complete descriptions of the armies, special characters, terrain, and other interesting features to guarantee you hours of fun on a grand scale are included in each adventure.

An adventure for 6-8 Characters Levels 1-15 and up