Martial arts, throughout the vast worlds there existed many forms and techniques of ancient martial arts, some even lost due to time, some even dubbed as taboo to practice, like the blood vein technique, it's said that this technique requires one to pierce their veins with needles infused with some special medicine, though initially, this did have its benefits, however, within a year the users were said to have gone out of control, their bloodlust was increased tenfold and the individuals were said to have lost their morality as well.
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