Nightmare was fed up being a hero. So, he possessed Ben's vision and tell untrue stories through its dream. Nightmare possessed Ben, through the Omnitrix. Nightmare in the Omnitrix, escaped outside the Omnitrix. Nightmare then, possessed Death Devil. Death Devil caused Nightmare to transform into Devil. Devil attacked Ben. Ben thought it wasn't his Devil transformation. He activated the Omnitri, saw that Nightmare and Devil slots were gone! He transformed in Technosquid. He merged with Devil. By the power of the possessed Death Devil, Gwen was absorbed by Devil. Ben changes into Sycorax. Devil abosrbed all the energies from the Omnitrix and release a virus (like in Omnivirus Part One). Omnitrix caused Nightmare into mixture of (Diamondhead, Waybig, Pink Magic, Rath, Spidermonkey, Pum, Humongasaur, Upchuck and Sycorax). What can Ben do to the virus, Uh oh?