In The Forge of Creation, in order to stop Aggregor from absorbing the powers of a newborn Celestialsapien, Kevin had no choice but to absorb the Ultimatrix's powers and turn into, as Vilgax would call it, a misshapen chaotic amalgam form of the creatures of the Ultimatrix. This form, dubbed Ultimate Kevin, is very powerful and easily defeated Ultimate Aggregor and drained his powers. However, Kevin's personality has become even worse than it was in the original series. In Night of the Living Nightmare, Ultimate Kevin appeared in a dream, trying to convince Ben to surrender the Ultimatrix.