In general, the tendency of people suffering some sort of abnormal condition to develop highly visible, off-color veins all over their body or near the distressed areas. Might be due to catching a bite from someone/thing infected with The Virus, or as a manifestation of a villain's Red Right Hand after willingly succumbing to The Dark Side or The Corruption. It's also possible if the character is suffering a Superpower Meltdown, Power Degeneration, or as a side effect to taking too much Psycho Serum. A vampire, werewolf or other supernatural critter hit with Depleted Phlebotinum Shells inducing a burning reaction (or even just partial sun exposure/blood starvation) may develop Tainted Veins because their glamour is failing. Special mention goes to zombie bites for always creating nasty nec