Capítulo 907: Ragnarok II

Its mouth is gagged by a titanic sword after Fenrir bit the hand of the god Tyr as he tries to put the chain on it.

Fenrir is bound to a magical rock that was infused with the water from Mimr Well and blessed by the forces of fate and destiny.

But, in Ragnarok, the wolf is released. And now, it is fighting with Odin Allfather in a story that is predetermined 

Loki saw how Fenrir fought Odin toe to toe. But Odin is more powerful than Fenrir. Fenrir who is now jumping across stars devours the suns of the Universe.

Its energy skyrocketed, its wound healed and then it turns back to fight Odin. No matter how Odin uses his spells and his magic, no matter how many times Odin pierce the wolf with his mystical spear, Fenrir healed extremely fast. 

But, it is not entirely because Fenrir is powerful that it could ignore most of the damage levied on it

Loki could see there is a force helping Fenrir. 

'Destiny and Fate' Loki muttered to himself.