Surt is a fire wolf and secondary character in The Niflheim+.
When he was a young wolf, Surt was fearful of humans because they were always hunting for his valuable red fur. After forming a close bond with Leo, a potential romance option in The Niflheim+, he grew to be strong and faithful. He has guarded and remained by Leo's side for over 1,000 years in Muspelheim.
Surt was born in a cold country located in the mountains. He was a wolf with red fur, which was rare and thus, highly sought after by hunters. When Surt approached a small village at the bottom of the mountains, he met Leo, a small child at the time, and grew very attached to him. Initially, he was welcome by the rest of the village until an especially harsh winter season wreaked havoc on the villagers. The villagers then accused Surt of being the cause of their misfortune and attempted to kill him as a sacrifice to the gods. Leo however, wouldn't allow it and tried to protect Surt on his own. When they escaped the village, they succumbed to the frigid climate and died together in the snow.
When Leo was reborn, he became a fire wolf. Both Leo and Surt were reborn in Muspelheim, also known as the Blazing Kingdom, where it is always warm and sunny in contrast to the snowy village. Upon their arrival, Muspelheim was desolate until more people appeared and it developed into a complete kingdom.
- Leo was the one who named Surt.