Shimmer is a strong, corrosive technical compound that resembles serum and has several applications. It was sold and distributed as a street narcotic during Silco's rule over the undercity and has been favored by Zaun's youth.
From a species of sparkling purple flowers he discovered in the caves of Zaun, Singed created Shimmer. Rio, his Waverider, a pet, was his first documented test subject. He would ultimately collaborate with Silco for several years before the medicine was completed.