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Sarutobi Asuma's Death (Naruto Shippuden)

I chose this because well after just loosing the 3 Hokage (Sarutobi Senoir) not to long after we see another Sarutobi go down, Asuma was loved by many and even had a baby on the way (Kurenei) but in order to protect his friends, family, and village he put his life on the line to protect it. Asuma was killed by the Akatsuki and trust me his students get there revenge. 

watch the vid here