Err, no specific examples. I’m just brainstorming on the fly.
More detailed notions that might help…
Give each player control over different sections of the battle/army. Perhaps one is in charge of the front line, another the left flank, another the archery division, etc.
Definitely run nested skill challenges. Have each player serve as the primary focus of his/her own skill challenge to represent how his section of the army does. Perhaps his adjacent allies can provide extra successes with smart tactical ideas or aid another roles.
Expand the win/loss count from standard skill challenges. Get a notion of how many opponents are on each side of section of the fight. Perhaps each success means 100 dead enemies, a failure means 100 dead allies. Just throwing out highly random numbers.
Primary “skill” for these would be attack rolls of course. For the most part, powers wouldn’t be helpful unless you want to provide a bit of leeway and argue certain area effect powers can be extended to larger areas for the battle. I’d recommend against it only because it will produce imbalance between controllers and other roles.
I would let players use other skills inventively to try for additional successes. Perhaps a tricky tactic to outmaneuver opponents – Bluff check. Demoralizing tactics – Intimidate. Decide what successes on these produce, but you could keep it simple and presume they just lead to deaths as well. Also remember that skill DCs would need to be higher than attack DCs in a skill challenge to keep things balanced (if I’m remembering my math right).
Back to the nested skill challenges. The idea would be that the skill challenges of the individuals contribute successes to an overall skill challenge. So a win on the right flank becomes a success for the overall battle. Determine the win/loss count as needed.
Hopefully this is helpful. Happy to spew out more ideas if/when they come to me if you find this of use
