Datamining on the 10.0.7 PTR has revealed data strings that suggest that an Envoy system may be imminent for the major factions in Dragonflight. Such a system would likely allow a character to earn additional Renown for a specific faction on a daily basis. The strings suggest that your character can choose to be an Envoy for one of the main factions for the day.
NEW PLAYER_CHOICE_ENVOY_TUSKARR Are you sure you wish to start helping Iskaara Tuskarr today? NEW PLAYER_CHOICE_ENVOY_VALDRAKKEN Are you sure you wish to start helping Valdrakken Accord today? NEW PLAYER_CHOICE_ENVOY_CENTAUR Are you sure you wish to start helping Maruuk Centaur today? NEW PLAYER_CHOICE_ENVOY_EXPLORERS Are you sure you wish to start helping Dragonscale Expedition today?Systems like this are not new to World of Warcraft, indeed the Wrathion/Sabellian weekly, Allegiance to One, is just such a system with the character choosing to support one of the two factions primarily for the week. This does not preclude the character from earning reputation for the other faction, it just provides bonus reputation for the chosen faction. In Mists of Pandaria, to help with alts and reputation farming, a commendation token such as Grand Commendation of the Shado-Pan could be purchased at Revered for each faction. This unlocked a 100% bonus reputation gain for all characters on the account. In Wrath of the Lich King and Cataclysm, the very popular tabard system, where wearing a faction's tabard would grant a character bonus reputation for that character, was similar in principal. We don't yet know what the envoy system for Dragonflight will look like, but the datamined strings suggest that it will be a daily choice, and possibly character specific.
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