Hearthstone Mercenaries: Appearance Rate of Mysterious Stangers changed
Till today, the fastest way to grind in Hearthstone Mercenaries was to play the Barrens Bonties Heroic and Pick the Level 8 Bounty, as you will always encounter a Mystery quick & easy.
But.. this does not work anymore, as mentioned in the Hearthstone Forum by a Dev.
We are adjusting the appearance rate of Mysterious Stangers to be based on the relative level of the strongest Mercenary in your party compared to the suggested level of the Bounty.