The phrase "Survival of the fittest" isn't just a well-known product of Darwinism, but a way of life in the rough-and-tumble rap game. When Mobb Deep introduced that quote to hip-hop as the song of the same name on their 1995 sophomore album, The Infamous, they may have been referencing the endless struggle of navigating the concrete jungle, but the same stakes also apply to their craft of choice, which the pair learned first-hand in the years after the song's release.

The rules of engagement between artists vying for the highest slot on the food chain includes an ample amount of verbal—and, at times, physical—contact between one another, resulting in all out wars between opposing factions. Some of the more prominent examples of this are "The Bridge" wars between KRS-One's Boogie Down Productions and MC Shan's Juice Crew, LL Cool J's duel with Canibus, the epic showdown between Jay-Z and Nas, and, more recently, the memorable duel between Pusha-T and Drake.

However, throughout rap history, some rivalries between artists, groups and collectives were more subtle and devoid of blatant diss records, but were still intriguing enough to get the public chattering and salivating at the thought of both sides locking horns. These instances included coy references and slights that may have been overlooked upon first glance, but were veiled enough to claim plausible deniability. From rappers attempting to one-up each other to stolen flows and everything in between, the roots of these exchanges run the gamut, but made for some interesting moments and conversations for rap fans. Drake and Tory Lanez, Jadakiss and Jay-Z and Cassidy and Lloyd Banks are just a few of the instances that come to mind.

XXL highlights 12 memorable rivalries between rap artists that kept the competitive juices flowing.

See 12 Rap Rivalries That Caught Hip-Hop by Surprise

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