Shadow of the valley
A blood covered battle field. It was once a peaceful village known as the village hidden in the blood. Widely the known because of their ability to use a blood manipulating blood line trait. In battle they could draw a single drop of blood and kill an army. The village had all ways been peaceful but with the next great ninja war come it would be the deciding party.
The other villages never agreed on anything until they decided that the village hidden in blood must be destroyed. That night the village disappeared from the map. The villages use a sealing jutsus to weaken the village and stop their blood line. Without the power the village feel to its knees it did not matter how young or old they were all to die. During the fight the villages had brought their own weapon. To back stab the others. The slaughter continued for three days blood vs the villages, and village vs other villages at the end of the war te blood ninja were dead among the others few had made it. The village leader had sacrificed his own life to save his wife and son but they kept coming in last ditch effort the mother summoned a beast and gave her son to it the beast disappeared with the child. He's was the only one that lived that night
The land around the village had been stained with blood so bad the caused the trees to turn red. So it's called the crimson forest.