Two games of the same snakes and ladders game can last very different times, and the reason is almost always the board. Snakes and ladders boards decide the length, because the jumps decide how far a throw really takes you. I know this because I had to choose three layouts on purpose for my site. Below is the reasoning, with the numbers I can stand behind and a clear note of where I stop.
Why does the board matter more than the dice?
The die is the same on every board, a number from one to six. What changes is what waits at the end of that move. A ladder turns a throw into a leap. A snake turns it into a loss.
I calculated the average for one piece racing alone on the Classic layout: 39.23 throws to reach 100. Remove every snake and ladder and the figure falls to 33.33. Keep only the ladders and it falls to 21.84. Keep only the snakes and it climbs to 118.11. So the snakes add far more length than the ladders save. All of that belongs to the Classic layout with its own jumps.
How much can one jump change?
More than you would think. Take away the snake from 87 down to 24 and a lone piece saves 7.28 throws. Take away the ladder from 80 up to 100 and it would cost 19.77 more throws. A single ladder near the end is worth about twenty throws, because it turns the long wait for an exact finish into one landing. The ladder from 28 up to 84 would cost 10.38 throws if it went missing.
This is why a board with its ladders spread out feels brisk, and a board with a few high snakes feels like hard work.
What do the three boards do to the clock?
Ladder Garden has twelve ladders and five short snakes. Its games run roughly one third shorter than Classic. Snake Pit has eleven snakes and eight ladders, one of those snakes on 99, and its games run roughly one third longer. Those figures come from the target I set for each layout, based on the expected throws for a piece alone. Nobody has timed real tables on the new boards, so I will not give minutes.
Does a longer board give skill more room?
No, because there is no skill to give room to. Every throw is a number the table produces. A longer board spreads the luck over more turns, so the swings feel bigger and the end is harder to guess.
How does the number of players change the clock?
Here the Classic board again. With two players, about 26.3 rounds pass before somebody finishes. With four it is 19.3, and with eight it is 15.1. More players means fewer rounds, because the first finisher is the luckiest of more tries. But each round holds more turns, so the wait for your own throw grows.
Online, each turn is capped at 30 seconds, and the page lists the game at 10 to 25 minutes. A big table on the Pit sits near the top of that range. A pair on the Garden sits near the bottom.
Choosing a board by the clock
On Boardit the host picks the board before the game starts. You can play snakes and ladders online with friends for free, and shorten or stretch the evening with one choice: Garden when time is tight, Pit when it is not.
A paper board teaches the same lesson. Add ladders and the game shortens. Add snakes and it stretches, and by more than you expect.
What I do not know yet
I have no measured figure for how a match to three wins, or a six with an extra throw, changes these times. I would sooner say so than guess.
Ahmed Moaz builds Boardit, a free browser game site.