When she dusted the Dibney's, right? By crossing the streams...I mean the rings (sorry, Ghostbuster flashback there). When I saw that my first thought was we've seen how Geoff Johns has going to handle who comes back and who doesn't. Those who get killed by the various Corps combining will stay dead and those of the dead who don't will get revived. This way Tula/Aquagirl will remain dead and Dolphin (and Cerdian?) will come back - so Tempest will have only one mate to worry about. Frankly once Tempest was killed I knew he was coming back at least. Ditto with Aquaman himself and Martian Manhunter. They are characters with too much significance to DC.