These are my & Chris Peer's rules. They are designed as a supplemnt to "A Good Day To Die". This supplement covers inter-tribal skirmishes between Plains tribes. They also include rules for Mountain Men, Settlers, Eastern Indians, and the Regulars of Mexico and the United States. The rules are designed for forces of 5 to 20 figures per side. The emphasis is on simulating the unique approach of the Plains tribes to warfare. Included are rules for counting coup, scalping, rescuing dead, wounded, or unhorsed comrades, No-Flight and Contrary warriors. The basic game system used is Chris Peer's "A Good Day To Die" which divides figures into Killers, Warriors, Braves, Soldiers, Civilians, and Rabble. "War On The Plains" also contains force generation lists for every major and minor Plains and Rocky Mountain tribe as well as the inavders and fun campaign rules and a solitaire engine for the terminally bashful. Published by the Honourable Lead Boiler Suit Company. You need a copy of "A Good Day To Die as well to play "War On the Plains".
Greg Novak's excellent system for gaming the Indian Wars of the West on the tabletop. Emphasis is on small unit actions. For the Amerindians each unit in the game represents a band of warriors or non-combatants. For the Army troops of cavalry or companies of infantry. Each unit is rated for armament, morale/medicine, fieldcraft, horsemanship, movement, melee skills, etc. Yellow Ribbon simulates the unpredictability of Amerindian warriors well. Distinction is made between "controlled" and "uncontrolled" bands. Each band, whether "controlled" or "uncontrolled" also has so much medicine and when it is exhausted will quit the fight regardless of what is happening in the larger battle.
Excellent set of rules by Trevor Brabyn simulates the intertribal warfare among Maoris and also among Eastern Woodland Amerindians 1400-1800 A.D.. This rules set has been influential on my own development of my rules as it solves two problems I had been unable to; how to simulate the unpredictable and uncontrolled nature of Amerindian warfare and also how to make shooting less bloody. Designed for 50 to 100 figures per side (though I use 15 to 35 figures myself)it is not a skirmish game, (neither are my rules), but gives a skirmish "feel". The basic unit is the war-party (or hapu for Maoris) led by 1-4 "chiefs". Rules for palisades, feigned routs, and duels between chieftains exist. There is a supplement to introduce Europeans into the game. I use these rules for my Woodland Wars and Pacific Northwest games.
While the above three sets are really small-unit rules this is a set of true skirmish rules for the Old West ca. 1850-1890. They are by Steve Lawrence (author of War Paint)and put out by West Wind Games. The rules use Lawrence's trademark "quality die" system in which character's various skills are reflected in rolling either a D6, D8, D10, or D12. The game is very well thought out and especially suited to "Hollywoodesque" types of scenarios. The only real drawback is that Amerindians are not differentiated in how they fight from Euro-Americans which makes it hard to include them realistically unless house rules are introduced to appropriately modify their behavior or the player(s) running the Amerindians stay strictly "in character".