Commander Blanx and dictator Martler, on the surface, seem to have nothing in common aside from their Martian origins and thirst for power. However, both alien adversaries of mankind faced off against the Men of Steel in their respective universe, leading legions of their people to the third planet for the sun intent on conquest.
Blanx was the leader of the Desert Dwelling White Martians, who were the perpetual foes of the Green Martians, at the time led by J'onn Jon'zz the Martian Manhunter. Both vying to capture the potent power source known only as the Blue Flame which heated Mars-One, it was Blanx who defeated J'onn and banished him for thirteen years from their society. Shortly thereafter through a fluke of science, J'onn ended up on Earth-One and adopted the alter ego John Jones, police detective. Yet secretly, Jon'zz carried out on a career as a costumed crimefighter from behind the scenes. It was Blanx who tracked down his hated foe and with his White Martian force tried to capture Earth.
And decades earlier on Earth-Two, Martler was an ego-maniacal warlord who led his fellow Blue Martians (whom he referred to as Solaziz) that had led secluded lives from the more common Green Martians on their world. Seizing upon a scheme whereby they would utilize their superior weaponry versus the more backward humans of their neighboring world. Apparently, the Blue Martians had obsessed with viewing televised signals from Earth-Two which broadcast the exploits of Hitler's Nazi regime in Germany only a few years prior, and so these war mongers sought to replicate and perfect that madman's dream of total domination of humanity. Welles with nothing but his prop sword in hand made short work of the Solaziz, and enabled the actor to contact Superman.
Both dictators commanded legions... the White Martians possessed Kryptonian level powers on par with Superman while the Blue Martians appeared far more frail and weak then the citizens of Earth. Years later, after having conquered Mars-One, Blanx used his knowledge to fanatically unleash the unmitigated might of the Blue Flame. On Earth-Two, the Blue Flame was controlled by Doctor Mephisto and ultimately conquered by Superman's ally, the Spectre. Eventually, Blanx was apparently the last survivor of his race and perished while in battle with Jon'zz. As for Martler, after Superman made quick work of the dictator's space fleet trapping them in orbit around the Moon. Then the pair of humans exiled Martler on a solitary planetoid so as to no longer influence his race which seemed to retreat once he was out of the picture.