Suddenly, Fiamma of the Right’s right arm was severed at the shoulder.

He had been utterly unable to detect the activation of the magic for the strike or the preliminary signs of that activation. The attack fired at Fiamma from behind had mercilessly carved his body apart. His right arm was the symbol of his power. Having lost that arm, Fiamma screamed while scattering red blood across the white snow.

Toaru Majutsu no Index Vol.22 epilogue