MMR stands for Matchmaking Rating. It’s a number that represents your overall winrate. Hearthstone doesn’t show you your exact MMR, it can easily get very confusing for new players which is why there are ranks and leagues instead. The reason why two players could have very different MMR despite being at the exact same rank is based on the number of games a player plays. For example, Player A plays 4 matches and wins 3 to reach Gold 5, and Player B plays 10 matches and wins 6 to reach Gold 5. Both are at Gold 5, but there is a 15% gap in the winrate between Player A and Player B. I can only assume that Hearthstone also knows the MMR of players in previous seasons, so even when a legend player hasn’t played any games in a new season, the game knows not to match them up against a new player playing their first game.
MMR stands for Matchmaking Rating. It’s a number that represents your overall winrate. Hearthstone doesn’t show you your exact MMR, it can easily get very confusing for new players which is why there are ranks and leagues instead. The reason why two players could have very different MMR despite being at the exact same rank is based on the number of games a player plays. For example, Player A plays 4 matches and wins 3 to reach Gold 5, and Player B plays 10 matches and wins 6 to reach Gold 5. Both are at Gold 5, but there is a 15% gap in the winrate between Player A and Player B. I can only assume that Hearthstone also knows the MMR of players in previous seasons, so even when a legend player hasn’t played any games in a new season, the game knows not to match them up against a new player playing their first game.