Sinned Yrden is the opposite of Dennis Nedry
Sinned Yrden was created after Dennis attempted to fix the mistakes that caused the Jurassic Meme War. By stealing the embryos he prevented the creation of new meme monsters. While escaping though, he fell into a conveniently placed pool of meme juice. The meme juice split Dennis into two beings, one of good and one of evil. The one of evil was Sinned Yrden, the anti Dennis.
Sinned Yrden is a former member of the Memevengers. After Derp told him to give up on them, Sinned created the Nalceigne to destroy both Engieclan and the Memevengers. He is currently Derp's right hand man.