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The Illustrious 18: blackjack's most valuable deviations

The Illustrious 18 is Don Schlesinger's ranked list of the eighteen Hi-Lo index plays that capture most of the value of card counting — published in Blackjack Attack and still the standard set taught by every serious counting course. Learn these eighteen and you bank the large majority of what full deviation play is worth, without memorizing a hundred fringe indices. New to index plays? Start with blackjack deviations explained; for every index drawn into its strategy-chart cell, see the full deviation chart.

The full Illustrious 18 list, in order of value

Ranked by how much each play is worth — the first rows carry most of the money, so learn from the top down. Where the H17 and S17 indices differ, both are shown; the index play is what you do once the true count reaches the number, and basic strategy applies below it.

  1. 1.Insurance vs ATake at TC ≥ +3
  2. 2.16 vs 10Stand at TC ≥ 0
  3. 3.15 vs 10Stand at TC ≥ +4
  4. 4.10,10 vs 5Split at TC ≥ +5
  5. 5.10,10 vs 6Split at TC ≥ +4
  6. 6.10 vs 10Double at TC ≥ +4
  7. 7.12 vs 3Stand at TC ≥ +2
  8. 8.12 vs 2Stand at TC ≥ +3
  9. 9.11 vs ADouble at TC ≥ -1 (S17: Double at TC ≥ +1)
  10. 10.9 vs 2Double at TC ≥ +1
  11. 11.10 vs ADouble at TC ≥ +3 (S17: Double at TC ≥ +4)
  12. 12.9 vs 7Double at TC ≥ +3
  13. 13.16 vs 9Stand at TC ≥ +5
  14. 14.13 vs 2Stand at TC ≥ -1
  15. 15.12 vs 4Stand at TC ≥ 0
  16. 16.12 vs 5Stand at TC ≥ -2
  17. 17.12 vs 6Stand at TC ≥ -3 (S17: Stand at TC ≥ -1)
  18. 18.13 vs 3Stand at TC ≥ -2

Why the top of the list matters most

Insurance at true count +3 is #1 because it applies to every hand you hold the moment the dealer shows an ace — no other index comes up as often or swings as much money. The 16 vs 10 stand is #2 for the same reason: 16 against a ten is one of the most common stiff spots in the game, and the index flips it from hit to stand the moment the count is even slightly positive. Value falls off quickly after the first handful of rows, which is why partial study should always start at the top.

The Fab 4 surrenders

Schlesinger's companion list: the four late-surrender indices worth learning alongside the Illustrious 18. They only apply at tables that offer late surrender.

  • 14 vs 10Surrender at TC ≥ +3
  • 15 vs 9Surrender at TC ≥ +2
  • 15 vs 10Surrender at TC ≥ 0
  • 15 vs ASurrender at TC ≥ -1 (S17: Surrender at TC ≥ +1)
  • 16 vs 8Surrender at TC ≥ +4

Illustrious 18 questions, answered

Do I need to learn all eighteen?

No — the list is ranked so you don't have to. The first several plays carry most of the value; many successful counters play with the top ten or twelve and add the rest later. Learning them in rank order means every deviation you add is the most valuable one remaining.

Do the indices change with the rules?

A few do. Whether the dealer hits or stands on soft 17 moves a handful of indices — both variants are shown in the list above, and the deviation chart has a dedicated section for exactly which cells differ under S17.

Which counting system are these indices for?

Hi-Lo, using the true count (running count divided by decks remaining). Other counting systems publish their own index numbers — these values are not interchangeable across systems.

Practice them at a live table

Reading the list is the easy part — recalling the right index mid-shoe is what needs reps. The free blackjack trainer keeps a live Hi-Lo count and grades every decision against these exact indices as you play, with a deviation-practice mode that deals you straight into Illustrious 18 spots.