Mokkan is an anthropomorphic fox and the main villain on the Redwall series book, Marlfox.
Mokkan the Marlfox and his six brothers and sisters were born of the royal Marlfox family on the island of Castle Marl, along with their army of water rats. Mokkan, like all Marlfoxes, had grey fur and cold amber eyes, and wielded a small double-headed battle-axe under a dark cloak. Marlfoxes are legendary masters of stealth, and can use their natural camouflage to blend in with their surroundings and become virtually invisible. He was also very intelligent and unpredictable.
Mokkan was the smartest and most wicked of his siblings, and was the self-proclaimed leader as well. When they came to Mossflower Woods, searching for valuable items to steal for their mother, Queen Silth, they stumbled upon Redwall Abbey. Eventually two of Mokkan's siblings, Ascrod and Vannan, stole the Abbey's prized Tapestry of their hero, Martin the Warrior. The Marlfoxes planned to return to their island with it, but in a battle one of them was slain, and they all demanded vengeance. Except Mokkan; he had plans of his own. He tricked his siblings into letting him 'guard' the Tapestry, then took it and traveled back to Castle Marl alone, much to the fury of the abandoned Marlfoxes.
When Mokkan arrived back at the island, he found that Queen Silth had been murdered by his sister, Lantur, who had stayed behind to protect Queen Silth. Mokkan then subtly murdered Lantur, pretending it to be an accident and blaming it on the "Spirit of the lake." Mokkan claimed the throne for himself and became High King Mokkan, but the power went to his head, and he slowly became insane.
When a band of Redwall warriors stromed at the Island to both retrieve the Tapestry and free the many slaves that the Marlfoxes kept, Mokkan tried to escape on a boat across the lake, but one of his former slaves saw him and hurled a chain out at him. The chain caught around the Marlfox's neck and pulled him into the water, where he was quickly eaten by the many vicious pike fish that lived in the lake. All of his brothers and sisters were slain back at Redwall before his death, so Mokkan was the last of the Marlfoxes.