Red Resign was a form of match manipulation that commonly occured in Hero Battles on the days the Hero Battles Zaishen quest was offered. It was used to farm Zaishen Keys by repeatedly completing the Zaishen quest and turning it in. Often abbreviated "RR", Red Resign relied on player cooperation.
Red Resign functioned by abusing the mechanics of the Hero Battles rating system. Due to the fact that the player with the higher rating in a given rated match enters the match as the Red Team, and that players lose rating on a lost, abandoned, or resigned match and gain rating on any victorious match, players' ratings constantly fluctuated should they leave when they entered as the red team or won when they entered as the blue team.
Red Resign day was nerfed by removing Hero Battles from the game.