blood vengeance

revenge on the death of someone, retribution for someone's death

A feud is a long-running argument or fight between parties—often, through  guilt by association, groups of people, especially families or clans. Feuds tend to begin because one party (correctly or incorrectly) perceives itself to have been attacked, insulted or wronged by another. A long-running cycle of retaliation, often involving the original parties' family members and/or associates, then ensues. Feuds can last for generations.
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