Dan Lubin responds.
I worked on Galaxy’s Top-3 extension to their 21+3 side bet when I was at Galaxy Gaming a few years ago. The gaming product was invented by Derek Webb of Three Card Poker fame, and is distributed by Galaxy.
The Top-3 side bet is used to offer windfall-type payouts without the need for an electronic progressive on blackjack games that already use Galaxy Gaming’s 21+3’s base side bet.
The base 21+3 side bet is straightforward: It pays 9-1 on the spot when the player’s two starting cards plus the dealer’s up card form a 3-card flush or stronger. The added Top 3 side bet pays a windfall payout on rare 3-of-a-kinds and straight flushes in those three cards (the Top 3 bet hits 1 in 130 hands or so). By adding the Top 3 side bet to their base 21+3 bet, players now get the chance for a monster payout on these monster three-card hands.
Players typically bet $5 on the base 21+3 side bet and an extra dollar on the Top 3 bet, just in case.
The Top 3 side bet has a low hit rate in order to provide its huge payouts of 90-180-270 (for 3-of-a-kind, straight flush, and suited 3-of-a kind). House edge on the Top 3 bet is in the 10% range depending on the number of decks used, which is fair in light of its windfall payouts. By contrast, a progressive bet typically has around a 25% house edge.
(Also in this regard, don’t listen to a casino dealer when he or she tells you that some bet has a player advantage to it. If the lights are on in the casino and the crew is paid, you can assume otherwise.)
The base 21+3 side bet is required in order to make the extra Top 3 bet, but this is all right, as the base 21+3 side bet itself has only a 3.2% house edge with a typical six-deck shoe game, low and fair for a blackjack side bet. Playing both (a $5 21+3 bet and a $1 Top 3 bet), you’re looking at about a 4.3% total house edge total, a relative bargain for the action.
Galaxy also has a "21+3 Xtreme" version of the base side bet, which, with an ascending pay table is similar to Three Card Poker's Pair Plus bet, for higher payouts on rarer hands, so the Top 3 extra side bet isn’t used with Galaxy’s 21+3 Xtreme.
[This answer was provided by Dan Lubin, author of The Essentials of Casino Game Design. Out hot new book is for anyone who wants to know how casinos games are really put together and why. This is book is the real peek under the hood of all casino table games, especially the new ones you see every time you take a good long look around the pit.]
