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One-Roll Mass Combat


You’ve done it! You’ve been running your old-school game for months now, and your players have finally escaped the survival horror of the dungeon, amassed an impressive fortune, made a Name for themselves, and constructed their own stronghold. This is it: the endgame. Now they can start waging war and permanently reshaping your campaign world.

But how do you handle mass combat? You could break out your ancient and dusty copy of Gary Gygax’s Chainmail, and thereby stop playing an RPG and start playing a wargame. But maybe your players don’t want to learn a wargame. Maybe you just want a robust, simple, transparent way to resolve battles and determine casualties, so your players can keep their focus on their characters, their roleplaying, and shaping their fledgling domain as they see fit. That’s where this system comes in.

One-Roll Mass Combat is a simple framework for resolving mass battles in Old-School Essentials. It is not a wargame. It is for referees who want to resolve battles quickly and abstractly in a way that their players can nevertheless understand and engage with. It stands in the tradition of the War Machine from the 1984 Companion Set, but with a heck of a lot less math!

Features include:

  • Resolve mass battles and determine casualties with a single opposed roll.

  • Account for any kind of combatant, including monsters and other unusual troops. No need to painstakingly reshape statblocks into “units” or “stacks”; just quickly total up the strength of each army.

  • Battles can be resolved extremely fast if the player characters participate as ordinary combatants or officers.

  • Alternatively, the PCs can undertake special missions and pursue specific objectives amid the chaos of war. Detailed rules are provided for this, including rules for movement across the battlefield, random encounters, and evasion and pursuit. A table of 30 random encounters is provided.

  • 40 detailed special mission seeds are provided for the referee to shape into “battlefield adventures.” A table of twists is also included for even more variety.

  • The system seamlessly plugs into existing Old-School Essentials (B/X) mechanics, including domain taxes, strongholds, mercenary costs, and exploration rules.

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Reviews (1)
Discussions (2)
Customer avatar
Brandon G May 26, 2023 12:27 pm UTC
I did a video on this product on my YouTube channel, RPG Overviews, found here
Customer avatar
亮 ? May 20, 2023 5:46 pm UTC
This extended rule book is really well written! It should be chargeable!
Customer avatar
Christopher H May 22, 2023 8:03 pm UTC
Thank you!
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2.92 MB
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File Last Updated:
May 19, 2023
This title was added to our catalog on May 19, 2023.
Christopher Heatherington
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