The Flash: Season Zero — DC Comics
Issue: #9
It's just another day in Central City as The Flash battles The Hydro Hunter, a metahuman made entirely of water! "Smoak Signals," a special two-part adventure starring Arrow's Felicity Smoak starts here!
First appearances: The Hydro Hunter
Creators: Alex Antone, Deron Bennett, Kelsey Shannon, Marcus To, Andrew Kreisberg, Marc Guggenheim
Characters: Barry Allen, Ray Palmer, Felicity Smoak, The Hydro Hunter, Vibe, Killer Frost (Snow), Eobard Thawne
Story arcs: Smoak Signals