In the comics, Polka-Dot Man's colorful spots are actually tech-based weapons, but the character was given a rather freaky overhaul for his recent big-screen debut.
In The Suicide Squad, Abner Krill (David Dastmalchian) is revealed to be the son of a S.T.A.R. Labs scientist who exposed him and his siblings to an interdimensional virus in an attempt to turn them into superheroes. This resulted in Krill growing multicolored, glowing pustules all over his body, which he was then able to expel and use as highly-destructive projectiles.
In one early scene, Bloodsport (Idris Elba) gets a look at his Task Force X teammate pre-expulsion, and director James Gunn has now shared some BTS photos of Dastmalchian donning those Elephant Man-esque prosthetics for a makeup test.
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Unfortunately, the chances of us seeing Dastmalchian reprise the role are slim. Polky was one of the casualties of the battle of Corto Maltese, having been crushed by Starro the Conqueror after doing quite a bit of damage to the alien "invader" with his corrosive dots.