Speed Force
In "The Flash Rebirth" mini-series, Savitar was able to escape from the Speed Force. He was run down by the Flash (Barry Allen) but Savitar disintegrates when the Flash touches him, leaving only a pile of bones. It is revealed that Professor Zoom altered Barry's Speed Force connection to make the Flash shift in reverse, cursed to kill every Speed Force user with a single touch until a conflict between the Flash and Zoom. Savitar, Lady Savitar (Christina Alexandrova) and Johnny Quick have been killed by this effect.