Badass Ranks served as sort of an infinite progression mechanic in Borderlands 2. Completion of challenges and feats awarded the player with Badass Ranks, an optional percentage bonus to various stats like gun damage, reload speed, elemental effect chance, shield recharge delay, etc.
According to creative director Paul Sage, Badass Ranks return to Borderlands 3 in the form of Guardian Ranks and they’re bigger and better in every way. Along with serving as a post-game infinite progression mechanic, Guardian Ranks will provide the player with skills and different skins. Moreover, the Guardian Ranks are shared between all your characters. Meaning you don’t have to grind out each class separately to take the benefits of Guardian Ranks.
It will not be long before we get a chance to try out the new Guardian Ranks in Borderlands 3.