Bloodlines are passive boosts to a player's character that add damage increases in combat and elements to unlock different types of Jutsus. Some bloodlines also provide extra passives with special tags. You pick a D-Rank Bloodline at registration, and you can take special bloodline quests to upgrade your bloodline to a C Rank to eventually a B Rank. A-Rank bloodlines you can purchase outright at Wake Island, or you can purchase a random bloodline item in the black market.