Mutant Viking Monsters were first created by Dr. Wolf. After Wolf fled Dr. Rex's island, he came to Viking Island and the Skr-Ok Clan. As a specialist in merging forms of life to create hybrid mutants, and awed by the power of the Viking Monsters he encountered there, Dr. Wolf decided to try merging the Mutant Dinos and the Viking Monsters into a new mutant race, one that he could use to destroy Dr. Rex and take over the LEGO Planet on his own.
To be continued...
Dr. Wolf had the Skr-Ok clan go on expeditions to lands near Viking Island, find a Mutant Dino, and bring it back to Viking Island. This gave the Vikings a chance to enjoy themselves in battle, and Dr. Wolf a Dino to extract DNA from for the creation of the Mutant Viking Monsters.
As the monsters breed, the bizarre alterations to their bodies become more ingrained in the muscle structure, skeletal structure, and nervous system. Therefore, while one of the first-generation Wyvern Lizards would barely know how to use its wings, a third-generation one would be a pretty good flier. So the oldest surviving Mutant Viking Monsters look like two beasts glued together, but the younger ones look more like one creature.
The following specimens have been observed to exist:
- Fenris Lizard (or wolflizard): The body of a Fenris wolf, but with the long tail and head of the Lizard. A Fenris Lizard can run and jump like the wolf, and the tougher body makes it slightly more durable.
- Wyvern Lizard: A Mutant Lizard with the wings of a Wyvern on its back. There are subtle alterations to other parts of its form to make it more aerodynamic. They rarely have any power other than chameleon, something possibly done deliberately by Dr. Wolf.
- Pteranodon Serpent: A slightly smaller Sea Serpent with enlarged Pteranodon wings. They can "fly" underwater as well, and therefore often lurk in the ocean until prey passes by, then swoop up, chase it, and blast it with lightning bolts from its mouth.
- Nidhogg Raptor: A mutant Raptor with the wings, tail, and more powerful forelegs of the Nidhogg Dragon.
- Fafnir Rex: A Fafnir Dragon with the bulk of a T-Rex. It is impressive that it is able to fly, but the wings are very powerful. Probably due to the energy required to make it fly, however, it usually walks. In battle, it can emit very hot fire, hotter than normal dragon fire and the furnace of a T-Rex combined. Its other preferred attack is to fly, but use its bulk to smash everything around it.
- Ofnir Rex: The greatest of all the Mutant Viking Monsters. Only one was every mutated, and it is essentially a larger, armored version of the Fafnir Rex. The most destructive parts of the Ofnir and T-Rex have been merged into this.