At some point in your game, especially in High Fantasy or Space Opera, you are likely going to come across a situation where you want to run a big mass battle. The only problem there is, quite simply, how do you do it? Now some systems have rules for this (notably L5R, Burning Wheel that I've played) but even those can be kind of herky-jerky at times. So, today, let's talk about some ways we can run mass combats and have fun with them.
Shameless Self Promotion
Before I begin, I feel I should point out that I have a free generic clip-on system called "Unsung Heroes" that you can grab to use for large battle scenes. In that the players don't control their normal PCs but the hordes of faceless mooks that make up the rest of the army. This lets you split the group up to have each PC run a different aspect of the battle, but still have everyone involved in that scene or combat. It is designed for quick and simple, so it may be too simple for some people. Still, it may be worth a look.
Speaking of Hordes
The game Deathwatch introduced me to a fun concept that I rather like. Basically, you represent an entire group of enemies as one creature. It's attacks get more damage and are more likely to hit, but it has less attacks than say the 100 goblins that the horde represents. It does a good job of representing the lucky/hard hits that accrue over time when fighting a horde, while making the mass easier to handle as a whole. They work well and are also something to consider. Especially as they let you describe your PCs fighting through, dare I say it, hordes of enemies in a round. Hacking, cleaving, shooting, and spelling down the masses in front of them.
Longer Round Timers
While you are using hordes, might I also recommend increasing your round timers. Mass Battles have a tendency of taking hours if not days and weeks when a siege happens. Not something you can properly represent easily with your standard 6 second round timer. However, pooling enemies into hordes and increasing a round to say being 1/2 hour. Even just increasing it to a minute can help out (like in old school AD&D), and then have there be gaps of time between waves and other things to keep the players going.
Something I've been mentally toying with, and have even used a few times in my Deathwatch game, is a priority system. When I am going over an expanded period of time instead of using the normal round timer, I have the players give me their top 3 priorities in order. The first priority is what their main focus is, then their second focus, and finally their tertiary focus. So if I get "1. Kill 2. Hold the Gate 3. Protect Myself" then that character will get to do a lot of damage, have a fair chance of holding the gate, and get some but not a lot of damage mitigation.
On the other hand, what I have frequently gotten is "1. Protect others from harm. 2 Hold the gate. 3. Kill" in which case the player in question is taking a LOT of damage, but it is damage that is meant for other players. They are using a priority to sacrifice themselves for the team. Either because they can take it, or just for sheer heroics. It leads to interesting situations. Especially when someone forgets to, or purposely doesn't, mention that they want to protect themself, or help with killing the enemies.
What have you done to run mass battles in your game? Any tricks that worked particularly well? Any that fizzled out and led to doom and failure? Sound off in the comments.