It may sound easy in principle, but the strategy is surprisingly deep. (All solitaire games on pay out tokens, which you can redeem for an infinitesimal chance to win cash prizes.) The more 21s you get, the more tokens you win. You have to add every card to one of the slots, so sometimes you can’t help going bust. The goal is to make combinations adding up to exactly 21, by the rules of blackjack, in which all face cards are worth 10, and aces are either 1 or 11.
The premise of the game is laughably simple: you place the cards of a standard 52-card deck, one by one, into one of four slots. Many years ago, when I was a postdoc in Seattle, I got hooked on a game called Turbo 21, one of the many dumb, but often addictive, online games on.
