When Gwen and Ben was fighting Hex and Augur. Ben and Gwen were sent froth to time where they knew that they were in the same place as they were. (from Ben 10,000 episode) Suddenly, they were confronted by Dexter (from Dexter's lab) and Vilgax. Dexter was sent from another dimension by Ben 10,000. Ben 10,000 was retired and his son (mother is Julie) Ken was patrolling the Planet. Ken was Ken 10,000 with Azmuth to be his guide. Ken was in trouble after Silhouette broke in, the DNA Lab was destroyed thus Primus. Albermech cuts off the Millimatrix and Devilmatrix from power thus destroying Ben's Omimatrix and Ken's Millimatrix. Devlin's Devilmatrix ran out of control thus needs Gwen and Ben to help them. Ben (Alien Force) changes his Omimatrix (which was the Key to stop Vilgax, Albermech andd Silhouette). Eclipse, Kevin's sister and Ben needs to work together before the Black Hole consumes the entire Dimension and merge.
By Ben 10 (new aliens were completely lost during the time travel but appeared again in the present)
By Ben 10,000
By Ken 10,000