Different rules and features in Blackjack significantly impact gameplay, strategy, and the house edge. Variations like the number of decks used, payout ratios for a natural blackjack, and dealer rules on hitting or standing can shift the odds in favor of the player or the house. Features like doubling down, splitting pairs, and side bets also influence decision-making and potential payouts. Some variations offer more player-friendly options, while others tighten the rules to increase the house's advantage, ultimately affecting a player's long-term chances of winning.