A brief synapses:
Montana is a three person trump game based on spades. The basic Montana hand is dealt with four piles of thirteen cards each. Each dealer has the option to call a variety of games which involve different rules, or the dealer can make up a new game.
In Montana, the goal is to pick up an exact amount of tricks that you bid. If you gain more then your bid, you get zero points. If you get less then your bid, you get minus however many less tricks you picked up were then your original bid. You get the exact amount of points as you bid if you are successful.
In Montana, the two of Spades is the highest card in the Spades suit. In all other suits the ace is highest and two is lowest. In Spades it goes 3,4,5,6,7,8,9,10,Jack,Queen,King,Ace,Two. Spades is the trump suit and the highest Spade played wins the trick. If no Spades are played, then the highest card in the suit that was led wins. Spades cannot be played until a player has none of the suit that has been led. Once Spades has been "broken", then any player can lead a Spade. But Spades still cannot be thrown if a player has a card in whatever suit has been led.
Going Nil: You can bid nil. This bid means you will get no tricks. If you pick any tricks you get minus six. If you successfully bid nil you get six points.
Nil Note: A rule that dealer's can call that affects Nil is Unabomb. If the dealer says you can Unabomb, that means that if your nil is unsuccessful you can attempt to pick up tricks and change your negative point total. If you are able to get three tricks you get minus three, four tricks equals minus two, five tricks is minus one and you get zero if you get six tricks. Anything less then three is still minus six and anything over six is still zero. This is only if the Dealer enables the Unabomb rule.
Going Double Nil: You can bid Double Nil after you have heard the dealers rules but before you look at your card. Failure equals minus thirteen, success equals plus thirteen. You cannot Unabomb a double nil.
Generally, the low club is thrown from whoevers hand that has it to start the game. The other two player follow and whoever wins the hand leads the next hand. The game follows this way until all thirteen hands are played and then the hand is scored.
Generally, Montana is played until someone calls last round on their deal, and then each player has a chance to deal one more hand.
The winner is the person at the end of the game with the most points.
Helena- Each player turns in four cards to the dummy and gets four cards back. They do this together without mixing the discard cards. After each player has picked their cards, the twelve discards are mixed and the dummy plays. The remaining original dummy card opens the round.
NOTE: When the dummy plays it goes in order, without prejudice to what has been played. It wins randomly and creates a chaotic feel to the game. In games where the dummy plays it is smart to take that into consideration when Bidding.
Whitefish- Hold 'em. No switching of cards, play them as they are dealt. This is straight Montana.
Smoked Whitefish- Hold 'em. Dummy plays. Low club starts.
Missoula- Four cards exchanged by each player to the middle. Then after the bidding, each player passes one card to the right and then their is another bidding session where each player can adjust their original bid up or down one trick.
Butte- Each player passes two to the right and two to the left, integrates the cards, and then exchanges four to the middle.
Great Falls- Each player is dealt seventeen cards. The dummy is dealt one card. Everyone drops four to the dummy and the dummy plays with the dealt dummy card opening the game. (This game also has a variation called Great Great Falls, where everyone exchanges two more with the dummy pile (excluding the original dummy card), after the first four are dropped.)
Billings- Each player exchanges four cards to the middle, then the dummy is shuffled and each player exchanges four cards again.
Bozeman- Each player exchanges two cards to the middle and pulls four out. Then with fifteen cards each, thirteen tricks are played. The final two cards are a blackjack hand that is worth one point on top of everything else. You cannot save cards by not playing them if that suit has been led and you have nothing else.
Continental Divide- If the dealer invokes the Continental Divide with any game, that means the Dummy plays.
Ken's Rule (needs a new name FAST)-This rule means that if the dummy leadsa spade, no player can follow in suit. This gives the dummy a one in four chance of winning the first hand, which generally will mean someone will get "set", meaning not enough or too many tricks.