Starcraft2 Protoss Colossus

Reports of these vile robots are sketchy at best, but it seems the protoss scum have come up with another mobile engine of destruction. Towering over our troops in a sinister war of the worlds fashion, Colossi are armed with some kind of thermal lances cutting beams of fire through our forces. It seems however from our most recent reports that they are incapable of air attack so this is the weakness we have been looking for.