Sam felt his whole body go numb. For some reason, this paralytic poison is acting against his body.
Every time a poison entered the body, his Hydra bloodline always took over and assimilated the poison, he would escape without any harm done to his body.
But this time, for some reason, before the hydra bloodline could even do anything, his human bloodline, the human flesh of his body started absorbing it crazily and it is even opposing the hydra bloodline.
Generally, all the beast bloodlines Sam has in his body are completely superior to his human part and the combination of this many bloodlines should have already killed Sam by now. Every bloodline of that caliber will be trying their best to show that they are the superior ones.
