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Roulette-18

Introduction

I first heard of Roulette-18 at the 2014 Global Gaming Expo. It is similar to roulette, except has 19 different outcomes and is played with a 20-sided icosahedron instead of a wheel. You can find it at some of the Grosvenor casinos in the UK.


Actual Roulette-18 dice, kindly given to me at the Global Gaming Expo.

Rules

The game uses an icosahedron, which for the non-math nerds is one of the five platonic solids, in this case the one with 20 triangles. The die is numbered 0 to 19, plus a 00. If the 00 is rolled, then all bets have no action and the die is rolled again. The following bets are available on the outcome of the roll.

  • Straight up: Bet on an individual number. Pays 17 to 1.
  • Split: Bet on two adjacent numbers of the betting payout. Pays 8 to 1.
  • Street: Bet on a row of three numbers of the betting payout. Pays 5 to 1.
  • Corner: Bet on four adjacent numbers of the betting payout. Pays 7 to 2.
  • Line: Bet on six adjacent numbers of the betting payout. Pays 2 to 1.
  • Odd: Bet on all the odd numbers. Pays 1 to 1.
  • Even: Bet on all the even numbers. Pays 1 to 1.
  • 1-9: Bet on the number 1 to 9. Pays 1 to 1.
  • 10-18: Bet on the number 10 to 18. Pays 1 to 1.
  • Red: Bet on the nine red numbers. Pays 1 to 1.
  • Black: Bet on the nine black numbers. Pays 1 to 1.


Analysis

The following tables show the analysis of each bet. The double-zero is ignored because all bets continue to have action after a double-zero is rolled.

Straight Up

Event Pays Numbers Probability Return
Win 17 1 0.052632 0.894737
Loss -1 18 0.947368 -0.947368
Total 19 1.000000 -0.052632


Split

Event Pays Numbers Probability Return
Win 8 2 0.105263 0.842105
Loss -1 17 0.894737 -0.894737
Total 19 1.000000 -0.052632


Street

Event Pays Numbers Probability Return
Win 5 3 0.157895 0.789474
Loss -1 16 0.842105 -0.842105
Total 19 1.000000 -0.052632


Corner

Event Pays Numbers Probability Return
Win 3.5 4 0.210526 0.736842
Loss -1 15 0.789474 -0.789474
Total 19 1.000000 -0.052632


Line

Event Pays Numbers Probability Return
Win 2 6 0.315789 0.631579
Loss -1 13 0.684211 -0.684211
Total 19 1.000000 -0.052632


All Even Money Bets

Event Pays Numbers Probability Return
Win 1 9 0.473684 0.473684
Zero -0.5 1 0.052632 -0.026316
Loss -1 9 0.473684 -0.473684
Total 19 1.000000 -0.026316


Strategy

All even money bets have a rule that if the die lands on zero then the player loses half only. This cuts the house edge in half from 5.26% to 2.63%. Thus, much like in European roulette, my advice is to stick to the even money bets only.

Rule Card

Here is a scan of the rule card.