I ran Mars Needs Steam at CelestiCon in
What I set out to do was have an adventure game on the table. "Adventure game" has broad as well as narrow meanings, so to be clear I wanted a miniatures game with strong role-playing elements and an element of surprise and discovery which went beyond a standard war game. That said, I also wanted its structure to be familiar as a wargame and playable as such and, most importantly, I wanted it playable without a referee, In other words, the game should not require a referee to invent an elaborate scenario with a lot of referee-generated surprises. Ideally, two players should be able to sit down, set up a gaming table, put their troops on it, and play -- say in a game store or in one of their gaming rooms -- on short notice and with a minimum of preparation.
The core "adventure" mechanism I used was borrowed from my pals Glenn Kidd and Frank "Don Franko" Sciuli; they developed it for use in their pulp game White
The wonder cards include attacks by wild animals (one of the reasons I'm glad Highlander Studios is doing animals), encounters with local Martians, exotic plants (which may p[rove dangerous as well), artifacts of the vanished Martian civilization, genuine treasure, a lost explorer or Martian princess, etc. All of them have a point value. In addition, the dangerous ones will attack and players have to overcome them to gain the points.
Where the role-playing bit comes in is with the characters available to a player/party. Usually a group will have two or three special characters which affect the types of military units the party can have, but they also may have skills useful in dealing with wonders/encounters. Characters with Animal Lore have a better chance of surprising wild animals, as opposed to the wild animals attacking the party first from ambush. Characters with Botany skill have better luck with exotic plants, and they also receive more victory points for finding those sorts of cards. Archaeologists receive more points for artifacts, a native guide can turn a hostile Martian native encounter into a potential additional friendly unit, etc.
Of course, it is also a competitive war game, so in addition to the encounters, players have to deal with their opponents, and you gain points for beating enemy units as well.
The scenario I ran had a party of British against a party of Italians (the Victorian era troops available were twenty Indian Army infantry and about twenty-five Italian Bersaglieri). The Italians had two army officers, a naturalist, and an archaeologist. The British had an army officer, a hunter, a spy, and a naturalist (as I recall). The spy is an interesting character. At on point during the game one soldier (not a character) of the enemy changes sides, usually with exciting effect.
That was about all there was to the game I ran, and everyone had a great time -- the cries of anguish and hoots of excitement drew a small crowd of onlookers as well. What that game did not have, which the game itself will, was exotic Steampunk vehicles and weapons. That's coming next.
The game uses point-based military units, so both armies are balanced on points. The characters chosen allow you access to different types of units, but no more points, so you still have tp pick and choose. A Mechanic gets access to ground vehicles, an Aerial Mechanic to flyers, and an inventor lets you design your own exotic vehicle or weapon. The vehicle and weapon design rules are simple and provide the game point costs of the various characteristics of vehicles and weapons -- sort of like a shopping lost with prices attached. It's a little more involved than that, but not much.
The game is obviously set in the Space: 1889 universe, but there is no reason you cannot expand it beyond that. The vehicle and weapon design systems are open-ended, and if you can describe the game effects of a weapon, you can determine its point value. By the same token, the game's Wonder Cards are created with a Martian background, but I'm sure I'll be doing expansions (cards and army lists) for Venus, Luna, and Earth -- different parts of Earth probably.