Heatblast

Heatblast is a Pyronite (pyro- meaning fire) from the star Pyros, a humanoid magma based life-form with the ability to control heat at will in various ways, including flight by firing at the ground to propel himself like a rocket. Pyronites are unable to lower their own body temperature, which prevents them from touching anything not fire-proof. They only seem to be weak against sufficient amounts of water or similar fire-extinguishing materials that may nullify their attacks and, circumstantially, extinguish them permanently.


Heatblast is Ben's first transformation, accidentally activated in the pilot episode of the original series, "And Then There Were 10" when Ben was trying to remove the Omnitrix immediately after it first attached to him. During the original series, when Ben caught a cold, it effected Heatblast by giving him cryokinetic powers instead of the normal pyrokinesis. Ben later regained access to Heatblast in Ben 10: Ultimate Alien, with his 11-year old self's Heatblast form making an appearance in "The Forge of Creation".


In Omniverse, for both Bens, he looks the same as in Ultimate Alien, only his eyes are once again connected to the fire on his head, his shoulder plates slightly tilt up and the 16-year-old Heatblast is taller and much more muscular. He first reappears in "A Jolt from the Past" trying to catch Corvo.


Source: http://en.wikipedia.org/wiki/List_of_Ben_10_aliens#Heatblast

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