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Tear Jerker: Buddha
"There is no fortunate being in this world!"
The very first story of the series tells of a rabbit, a fox and a bear searching for food in order to feed a starving old man. While the fox and bear are successful, the rabbit isn't. Returning empty-pawed, he gets the others to build a fire, reveals that he will sacrifice his life so that the man can eat HIM, and throws himself onto the fire. While the man puts the fire out, it's too late, and the others mourn while the rabbit's spirit ascends to Heaven.
In Volume 2, Siddhartha goes into a trance and lives the life of a small bird. As he describes it to his parents, he tells them about his dear mate and their unborn children, killed by humans. She was so sweet, mother.
Tatta. He grows up discriminated against, his family is burned alive, the woman who became as his mother and the boy who was as his brother are killed. And then he has his ninth birthday. And then, after becoming the Buddha's first diciple, he forsakes his master's teachings and is killed.
Buddha himself after Tatta dies. He has a heart-wrenching breakdown, described in the narration "Buddha was the most grief-stricken of them all. Not only had his people been exterminated, but in the end, it seemed that not a single word of his teachings had done any good. Not for the Shakya, not for Tatta, his very first follower."
Devadatta: Only his mother loved him as he grew up, as he was a bastard. Then he is accused of demonic posession and cast out of human society. When he returns, he is used by an old woman as a spy. Eventually he meets Buddha, but instead of apprecating him as most others did, he became homicidaly jealous, trying to kill him. Eventually, this led to his own accidental suicide, still angry.
When the Crystal Prince finally expresses love for his mother - after she's dead because he ordered her slave pen, already infected with the black death, to be burned.
The story of the king deer who gave himself up to the humans to save a pregnant doe.
The destruction of the Shakya in Volume 8.
Chapra and his entire story in Volume 1. Raised a slave, he meets and is freed by Tatta. Then he is adopted by a general and accepted into warrior culture; things are looking up. But then, his parenthood is revealed. His beloved is forced by her father to turn her back on him, his adopted father is cut out of society, and to top it all off, he and his mother are killed. A Shoot the Shaggy Dog story at it's finest.