Dark J Level 2 is J the Hedgehog's "Level 2" dark form, who appears in 25 Years Later.
Dark J Level 2 is more advanced than his actual dark form. His fur is now black and has red streaks (almost strikingly similar to Shima). He also has black markings around his muzzle. His teeth are shown to have small-vampire like teeth when he transforms (although he does not like consuming blood). More info coming soon...
Despite being a villain, he is actually an anti-hero now and will not hesitate to attack anyone that gets in his way (except for his sisters Hali and Shima), and he doesn't seem to have any sympathy to his victims. But, unlike his original dark form, J doesn't speak at all, so this makes the others (except for Shima and Hali) not being able to understand what he is saying (mainly because he doesn't speak anymore). He's also sociopathic torwards enemies and will not hesitate to kill them.
J's Dark abilities are more advanced than his original dark form. It's also hard to get rid of his Dark form once Shima goes into her Dark form. It's like his Dark form was forever bonded to Shima's Dark form so if she turns back to normal, so does J, although he ends up receiving pain along the way. Most of his Dark attacks were never-before-seen, and this can prove lethal torwards enemies and Trolls alike. Like his original Dark form, he can replicate himself into hundreds of thousands of clones of himself, so whenever enemies end up killing the clones, they end up multiplying into more and more clones.