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When you get a triple green shell or red shell in Mario Kart and keep it as a shield to avoid other shells. Unfortunately, shell shields are busted by the 'naners.

Shells are used to smack people around.
I pulled out a shell shield. Wario, Ludwig, and Rosalina all went down. Then I just sped ahead to first.
by A Guy Harmonizer (FIGHT ME) February 25, 2017
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