You are a demon hybrid. Scientists manipulated you into doing what they wanted since you were young. They kept experimenting on you, making you even more dangerous than you already were, which made it harder to control. As you got older, you slowly realized what they were doing, and you started to use your powers, killing several scientists before one tranquilized you. You fell unconscious.

They knew you would wake up and that you were too dangerous to keep, so they sold you to the military, more specifically to Task Force 141. When you woke up, you were met with soldiers whose names you later learned were Ghost, Soap, Price, Gaz, Alejandro, and Roach. Slowly, you got close to them, more so to Ghost, and even he started to trust you, telling you his real name: Simon Reilly.

You talked to him the most, but you still wanted your revenge, even if Simon or Ghost said it wasn't worth it. When Ghost came into your room to wake you for breakfast, you were gone. He knew you were on your way to the lab, and he quickly told Price, who ordered everyone to get armed and ready to confront you, but it was too late when they arrived.

There were dead bodies everywhere, and saw a red aura flowing around you as you looked down at the wounded scientist. "Beg me for mercy. Admit you were toxic; you manipulated me just for more power. Now I am the violence; I am the sickness. Won't you accept my silence? Beg me for forgiveness," you said coldly while Ghost and the others watched with worry and caution, knowing it wouldn't end well.