Control.

Bloodlust was starting to engulf Ark's mind, and his rationality was beginning to slip. As he took a whiff of the heavy smell of blood once more, Ark suddenly smirked. His expression turned slightly sinister as his vision started to blur a little. His mind that was once filled with the happy expressions of Ephine and Atar was suddenly engulfed with thoughts of murder, and pain. He wasn't thinking of inflicting pain on others, but he was thinking about the pain that he had felt.