THE GAME WITHIN THE GAME

One of the things that comes up in most RPGs eventually is the game within the game: chess, gambling, darts, knucklebones, etc. A lot of times this can just be hand waved with a roll, or even just a quick comparison of character's stats. Sometimes you may actually want to take out the chess board and play the game if the stakes are high enough. But that can time consuming, and is certainly not everyone's cup of tea. An alternative is for the GM to come up with a faster analog to simulate the game in question and give the players a sense of investment. Most of the time, I frankly think a quick roll is sufficient, but there are times when I opt for one of the latter two (usually when there is a lot at stake and people seem interested in the action of the game within game itself).

The second option is the simplest in terms of prep. If the players are engaged in chess, you pull out the chess board. If they are playing black jack, you pull out the deck of cards, etc. Something like chess is usually too time consuming, but black jack is pretty manageable. Personally if I were a player in a James Bond-style spy campaign, I would probably like to actually play some cards in a casino situation rather than reduce it to a single roll or some other subsystem using skills. 

Before converting chess into a series of skill rolls or some other abstraction, consider simplifying it. There is no reason you have to play a whole game of chess, you could just play 2-3 moves. One way to achieve this is for the GM to set up the board before hand positioning the pieces so either side has a good shot at winning in the next three moves. Obviously setting up so things are fair for the player is the key. Or you could arrange the board according to skill comparisons or attribute comparisons. For example, if the NPC in question has a high intelligence and the PC an average intelligence, you might choose an arrangement that favors the NPC's side of the board, or vice versa. 

Simplifying has worked well for me. There is a Roman game called Tali, and I used a simplified form of it for my Servants of Gaius campaign using d4s. Here are my notes on the method: 

Tali

The favored game at the House of Fortuna is Tali (or knucklebones) which uses four rectanglular 4-sided dice (made of glass or bone). Each side has a number on it, 1, 3, 4 or 6. The best roll is called a Venus throw and the lowest called Dogs. While all kinds of combinations are possible, only four results matter for obtaining a win (from highest to lowest): Venus (6,4,3,1), Senio (6 and any other combination: 6,3,3,1), Vultures (all the same result except ones: i.e. 4,4,4,4;3,3,3,3, or 6,6,6,6) and Dogs (all 1s). Whoever gets the highest category on a roll wins the pot (on ties the numeric values of the dice are counted between the tied rollers and the one with the highest result wins).

The players may want to play a game of Tali for money (usually the pot starts at two hundred sesterces and works its way up). To simulate the four sided die use d4s and replace the above groupings with the following:

Venus: 4,3,2,1

Senio: 4 and anything

Vultures: Four of the same except ones (4,4,4,4)

Dogs: all ones (1,1,1,1)

This is quite simplified but close to how the game may have been played (there is some debate on what Tali actually involved and how it was scored). Being a simple dice game having the players actually roll made sense. I suppose I could ask for a Skill roll instead, but if they are going to roll dice anyways why not shift it to a 1-1 match of what their character is doing? Of course if they wanted to cheat, that might require some use of the skill system.