The variety's name was initially UEB 32642 when it was introduced in 1999, and over time, it was rebranded to Opal apples. After their release, Opal apples were further studied in over 63 orchards across Europe and were introduced to the United States in 2010.

According to the official opal apple webpage, the apples are a cross between Golden Delicious and Topaz. They were discovered in 1999, tested in 63 orchards throughout Europe and the Mediterranean for 12 years, and introduced to the US market in 2010.

Pluribus's self-play produces a strategy for the entire game offline, which we refer to as the blueprint strategy. Then during actual play against opponents, Pluribus improves upon the blueprint strategy by searching for a better strategy in real time for the situations in which it finds itself during the game.

The royal flush is a case of the straight flush. It can be formed 4 ways (one for each suit), giving it a probability of 0.000154% and odds of 649,739 : 1.