In the comics, Geomancer is foe of the Justice Society's, co-created by DC Chief Creative Officer and The Flash executive producer Geoff Johns. Adam Fells was a big fish in a small pond until he joined up with the Injustice Society and bad things started to befall him, building to his death. A successor came along, taking up the name and costume, but didn't make many appearances before the New 52 reboot.
In the TV series, Geomancer is described as "a dangerous meta-human with the unique ability to create earthquakes. Intent on destroying the Flash, Geomancer uses his powers to unleash a string of targeted earthquakes, optimistic that he’ll draw out the Flash for a mano-a-mano fight to see who’s the most powerful metahuman in Central City."