Learn about poker hands and values in games available at PokerStars, The best possible straight flush is known as a royal flush, which consists of the ace. Insane Poker Hands!!! Royal Straight Flush vs Quad Aces!!! raphaelhalim .. Oh BJ Penn is playing poker. Royal Straight Flush. Noun. The straight flush A-K-Q-J suited. ADDITIONAL INFORMATION: Uncommon usage. More properly referred to as a royal flush.