Spanish 21 made its first appearance in 1990s -- long after the threat of card counting had become known to casinos. The designer team of Spanish 21, which included Julian Braun -- the legend who developed the original Hi--Lo indices --
must have intended to defeat or frustrate all card counters in order to make Spanish 21 more appealing to the fee-paying casino licensees.
Well, well, the Spanish 21 team wasn't 100% successful, but it had succeeded in rendering most, if not all, of the known blackjack card counting systems back then completely useless.
But as they say, when there is a will, there is a way. Katarina Walker tweaked Hi-Lo and turned it into a Spanish 21 card counting system as well. Hi-Lo therefore became the lone survivor. Quite a feat, Katarina single-handedly changed Hi-Lo from a "Balanced System" in blackjack to an "Unbalanced System" in Spanish 21.
AceMT was another story. Back then, AceMT was still a an unpublished private card counting system, so it couldn't possibly be on the designers' radar screen and and to be zapped. A lucky escape?
