Far away from the fort walls, where no one could see him, Luthor crouched a bit as he caught his breath. As a Foundation realm cultivator he did not have a massive reserve of spiritual energy, but what truly allowed him to use such massive attacks was the augmentation of his suit.
The suit, which had been designed specifically for him, replenished his spiritual energy almost passively. The moment he stopped channeling energy, even for a moment, it began to replenish his reserves.
That did not, however, mean that he could use energy endlessly. He had to master the extremely precise way in which to use techniques and his energy, keeping in mind how quickly it will replenish. After so long on the battlefield, he had already mastered the art.
