Gambling need not be all about luck. While luck does play a part, once the game offers the gambler alternatives during a game, then obviously one alternative has better odds than the rest. The online blackjack trainer "trains" the player by warning them if they choose an option that does not have the best odds of winning.
Blackjack actions are:
Depending on what the dealers face card is, and what the players first cards are, it's possible to make some guesses as to which option is best (hitting/standing/doubling/splitting/surrendering). The trainer lets the player select any legal action, and then informs them if the action they selected was not the best one based on the cards that have already been drawn and seen.
The information box that pops up to inform the player of a bad play has, in red letters, the table that the advice was taken from and the sum of the players cards at the point of taking the action. The tables are the following:
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