—Nightwolf to Cyrax in Mortal Kombat (2011).
- Mortal Kombat (2011): "Nightwolf is one of few Earthrealm mortals with a strong connection to the spirit world. A powerful Native American shaman, he is guided by the empyrean forces and communes with divine beings such as Haokah, known to the East as Raiden. Nightwolf's devotion allows the Spirits to work through him, granting him unnatural long life and ethereal weapons to kombat the darkness that threatens mortal-kind. In the coming crisis, however, it is not Nightwolf's arsenal that will alter fate. His faith in the Spirits will inspire those who have lost hope."
- Mortal Kombat 11: "Every generation, the Great Spirit chooses a worthy warrior to become Nightwolf: the Matoka’s champion and protector. Grey Cloud proved worthy when he laid down his life to prevent the Black Dragon from plundering what remained of his tribe’s sacred artifacts. As Nightwolf, Grey Cloud possesses extraordinary magic granted by the Great Spirit. He uses it not only to fight for the Matoka’s future, but also to defend all of Earthrealm."
Before becoming Nightwolf, he was once known as Grey Cloud from the tribe of Matoka. As Grey Cloud, he was born and grew up in poverty alongside his people, who were treated unfairly, which greatly upset him, adding to his frustrations over his beliefs, the tribe's ancestors had given up their descendants future to colonizers.
One day, Grey Cloud was approached by the Black Dragon leader, Kano, who offered to make Grey Cloud rich, in return for bringing him the Matoka's most sacred relics. Consumed by his anger, Grey Cloud agreed and attempted to steal the relic, but soon realized that he would be surrendering the last of his people's dignity.
Grey Cloud then turned against Kano and chose to defend the Matoka for the first time, but he was brutally beaten and left for dead. As he lay dying, the Great Spirit of his people came to him and empowered Grey Cloud, giving him the mantle of Nightwolf, the legendary defender of Matoka. As Nightwolf, he managed to fight back against Kano and successfully drove the Black Dragon away from Matoka.
Now attune to the spirits of Earthrealm, Nightwolf served to protect his people and his homeland, which drew the attentions of Earthrealm's protector god, Raiden, who made Nightwolf one of his champions to defend their realm against Outworld in Mortal Kombat.
Nightwolf appears during the first Mortal Kombat tournament. When Scorpion is brought out to fight, Nightwolf is his second opponent. Scorpion believes that Nightwolf dishonors his kind by not seeking retribution, and defeats him in battle. In certain intro dialogues in Mortal Kombat 11, Nightwolf claims that he lost to Scorpion on purpose.
Nightwolf is seen after Liu Kang successfully defeats Shang Tsung. Although he participated on Earthrealm's behalf, Nightwolf is not shown as having attended the ceremony for Liu Kang at the Wu Shi Academy.
Nightwolf does not appear again until the Earthrealm invasion. After Kurtis Stryker defeats Ermac in the Subway, Nightwolf appears and asks Stryker to join the Earthrealm warriors in an attempt to defeat Shao Kahn. Nightwolf then appears as Cyber Sub-Zero is reprogrammed. When Raiden receives another vision, Nightwolf asks Raiden what he has seen. The Earth warriors are informed of the Soulnado, and Nightwolf joins Cyber Sub-Zero in an attempt to stop Quan Chi. Nightwolf battles Quan Chi and defeats him, and then is attacked by Noob Saibot. Nightwolf defeats Noob and launches him into the Soulnado, causing it to disappear. Nightwolf returns to the Earth warriors with the news, but Raiden sees that his amulet is still breaking.
When the Lin Kuei cyborgs ambush the Earth warriors, Nightwolf faces Cyrax, then Sektor in kombat, defeating both. After all of the cyborgs are defeated, Sindel appears and begins to kill most of the Earth warriors. Nightwolf then faces Sindel, and eventually is forced to sacrifice his life to obliterate her vaporizing them both in a pillar of light. Nightwolf's soul is later seen in the possession of Quan Chi, and is defeated by Raiden.
Jax and Smoke are assigned to take out and guard the portal to Raiden's Sky Temple. The two, alongside some Netherrealm demons manage to kill the Shaolin guards and guard the cave. Johnny Cage, Sonya Blade, Kenshi, and a squad of soldiers prepare to jump Jax and Smoke but Nightwolf arrives at the cave via portal and announces the squadron's position to his Netherrealm allies. Nightwolf is then defeated by Kenshi while his allies, Smoke and Jax, are defeated by Johnny Cage.
Nearly three decades later, Nightwolf's next and final appearance in the game was when Quan Chi and his minions ride to the former's fortress to await D'Vorah's arrival with Shinnok's Amulet. They are then stopped on the way by Earthrealm forces (including Kenshi and now-human Jax) due to Sareena's tip-off. Nightwolf attempts to fight the soldiers by throwing tomahawks at them as a wounded Quan Chi is led to his fortress by Liu Kang, but ultimately retreats when Earthrealm gets the upperhand.
Unlike his revenant minions, he is not seen outside the Sky Temple before the Special Forces invaded it.
After Past Nightwolf defeats his Revenant self, Shang Tsung takes the Revenant Nightwolf’s soul to heal himself back up to full strength.
- Mortal Kombat (2011) (Non-Canonical): "It took all of Nightwolf's power to destroy Shao Kahn. His spirit guide, the wolf, had aided him in the battle, but in the aftermath its presence was no longer felt. Nightwolf returned to his home, seeking the elders' help in reconnecting to the spirit world. During their ritual, his wolf returned to him--changed. Shao Kahn had tethered his soul to the wolf spirit in order to cheat death. Now corrupted with Shao Kahn's evil, Nightwolf has transformed into his Animality, his bite converting his victims into subservient lycanthropes. Through Nightwolf, Shao Kahn will conquer Earthrealm one mortal at a time."
- Mortal Kombat 11 (Non-Canonical): "Before I was Nightwolf, I was a fool named Grey Cloud. Born into poverty, I resented my ancestors for giving up our future to colonizers... Kano offered a way out, promising riches if I stole the tribe's most sacred relics. I was sorely tempted, but then I realized that by saving myself, I'd be surrendering the last of my people's dignity. For the first time, I defended the Matoka's pride. Kano was unimpressed. But as I lay dying, the Great Spirit came to me. By rejecting Kano, I had proven worthy of an ancient honor. The mantle of Nightwolf... legendary defender of the Matoka. Now, as I inherit Kronika's mantle, the way before me is split. The Keeper of Time cannot also be my tribe's defender. Which path do I choose? Even here, at time's beginning, the Great Spirit's wisdom guides me. She calls me to restore history. The Matoka, I must leave to another. To the next Nightwolf. Like all our sacred relics, the Nightwolf mantle belongs to the tribe. Any Matokan, can prove worthy of its power. I enjoy imagining who will defend us next."