Originally designed for boring 5 mans but now supports raids as well if that's your thing. Recommended that everyone have the add-on but can be played with only one player running the add-on.
Blizzard's policy on gambling:
http://us.blizzard.com/support/article.xml?locale=en_US&articleId=27048
Keep in mind this game is more akin to a game of poker. There is no "house" for the odds to be stacked towards.
/gamble to hide/show the main window.
THE GAME
Group Gamble is simply a game of chance based on the items that drop in a standard instance. After an initial wager is placed by all the players, your contribution to the pot is increased whenever you win an item. At the same time, every item you win also increases your odds of winning the final pot.
This is a game played between friends. The final collection of the pot by the winner is based solely on honor. No one can force a loser to pay up but it's no fun if they don't. Also, there is no way to play this across servers due to the inability to trade gold between each other.
THE OBJECTIVE
Win the pot!
PLAY SUMMARY
1. The host sets his/her wage in the options menu.
2. The host checks the check boxes beside players who are going to play.
3. The host clicks the start button to start the game.
4. Players input their wager through chat or the popup box.
5. After all wagers are collected, add-on determines if it will be a high stakes round.
6. Add-on watches loot drops and increments player's contributions, pot size and final rolls appropriately.
7. When all loot is won and the instance is over, all players make a /random roll based on what the add-on says.
8. The host clicks on the winners name in the players list.
9. The add-on announces the winner, how much they won and how much each player owes.
10. Losers trade gold to winner.
INITIAL WAGER
When the start button is pressed your wager is determined by the number you chose in the options menu. All other players are then asked to send their wager to you in the form of a whisper, say or party chat. This wager must be between the min and max and be a multiple of 10. For every 10 gold you wager you are adding an additional 5 to your final minimum roll.
HIGH STAKES
After all the initial wagers are collected, the game determines if it is time for a high stakes round. There are several variations: All items, Greens, Blues, Purples and non-player items. All item rounds are the most likely at 50% while the rest are a 12.5% chance each. A standard high stakes round applies a multiplier against appropriate items of its specific round type. e.g. A green high stakes round doubles the value of all green items that drop.
STREAKS
If by chance, you get a high stakes round one directly after another, the multipliers compound on each other and the 2nd round will be 4x the base cost per applicable item (a 3rd would be 8x).
DRY SPELLS
A dry spell is when you haven't had a high stakes round in a set amount of rounds (determined in the options). Once this has happened, the chance for a high stakes around is 5x the normal percent. If at anytime a high stakes round occurs, the dry spell is reset and starts to count games again from zero.
WINNING ITEMS
Once the game is underway you clear the instance as normal and the add-on watches for loot drops. When loot is obtained, the add-on automatically increases the winning players contribution by the appropriate amount (base item value * high stakes multiplier * double item multiplier) and increments their minimum roll by 10. The minimum roll increase is unaffected by the value of the item. If a non-player wins an item, every participating player puts the appropriate amount into the pot. Unfortunately no one has their minimum roll increase in this case.
DOUBLE ITEMS
Whenever an item is won there is a chance that it can be worth twice as much gold contributed. The minimum roll increase is not doubled.
FROZEN ORB
The [Frozen Orb] is a wild card. It has no contribution to the pot associated with it and only increases your minimum roll by 10. It can, however, become a double orb and add 20 instead if you're lucky enough.
FINAL ROLL
The final roll is a /random between your minimum and maximum numbers determined by the game. Whoever wins this roll wins the pot! The end of the game is determined when you click the winning players name in the player list. Keep this in mind and make sure all loot has been collected so that the rolls, pot contribution and pot are all accurate.
LOSING STREAKS
When you lose enough rounds in a row (5), you get a small bonus to your maximum roll for each loss beyond that point. A win will reset this bonus though it's unlikely to make up for the debt you have obtained.
ADD-ON COMMUNICATION
Only one person is required to have the add-on to actually play the game. In this case you can simply make sure the Party Chat check box is checked and any relevant information will be posted in party chat as the game progresses. If multiple players (preferably all) have the add-on, you can turn off the party chat function and instead the host player (the one who hits start) will send the information directly to everyone else's Gamble frame.
DEFINITIONS
Pot - The accumulated total of all gold players have contributed due to items won.
Initial Wager - The gold you bet to start the game. Every 10 gold is an additional 5 on your minimum roll. The initial wager is NOT affected by a high stakes round multiplier.
Roll - At the end of the game you make a final roll based on your minimum and maximum number. e.g. /random [min] [max] ; /random 35 100 ; /random 50 105.
High Stakes Round - A round of play where a specific category of items is doubled in value.
Streak - When consecutive high stakes rounds happen, each subsequent round is 2x the previous rounds item multiplier. e.g. 1st = 2x, 2nd = 4x, 3rd = 8x, 4th = 16x, etc.
Dry Spell - A series of regular rounds unbroken by high stakes rounds. When the minimum required rounds is met the chance for a high stakes round is 5x more likely until one occurs.
Double Item - An item worth 2x more on top of any multipliers being applied by the current round.
Frozen Orb - A special item that adds 10 to your minimum roll for free.
Double Orb - A [Frozen Orb] with a double item applied. Adds 20 to your minimum roll instead.
Host - The player that clicks start first. Any other players running the add-on will become clients that are updated directly from the hosts mod. Only the host can pause/resume the game, declare a winner or abandon a game. If a host leaves the party, everyone else's add-on is reset. The hosts game information also isn't reset upon DC or leaving the party so that it can be continued if necessary.