Blackjack

Nothing about the rules has been changed here: you're dealt two cards, the dealer shows one, and you decide whether to hit or stand while trying to land closer to 21 than they do without going over. What makes any version of Blackjack worth returning to is pacing and feel rather than new mechanics, since the game itself hasn't needed fixing in decades. The tense moment is always the same one, right before the next card flips.