|The name or term "David" refers to more than one character or idea. For a list of other meanings, see David (disambiguation).|
Captain David D. "Dave" Dubosky, aka Countdown, is a member of G.I. Joe. Serving as the Joe team's resident astronaut, Countdown is an expert pilot and electronics engineer, able to fly an F-16 with one hand and repair broken instruments with the other. Despite these incredible abilities, the rest of his teammates see him as incredibly boring.
Dave Dubosky was a member of G.I. Joe who later transferred to the Earth Defense Command. At some point however he was replaced by a Dire Wraith with his G.I. Joe dog tags being left at Mount Olympus.
When Rom landed on Earth, Dubosky infected the lone survivor of a military unit that had borne witness to the Space Knight's arrival. Dubosky met with some of his former G.I. Joe teammates to hunt down the Space Knight.
Dubosky later found and retrieved Darby Mason. When Dubosky questioned her about Rom, Mason remained coy about the details, unsure of whether to trust him. Dubosky gave her a special gun and phone to protect herself and get in contact with him. Mason later used that phone to report to Dubosky that she had found Camilla Byers and Rom.
At the base, Dubosky reached out the overeager Leonard Song and brought him to see Rom trapped in a dimensional binding prism. When Darby freed Rom however, Dubosky told Song to watch her while he went to confer with the Wraith growing within Byers. Pleased with the progress of its gestation, he "fled in terror" from Byers.
Countdown's G.I. Joe dog tags were later recovered from Mount Olympus by the current Action Man, Ian Noble, who received them from former G.I. Joe member Big Ben. Ian reported this to Mainframe, who insisted that Dubosky being there was impossible, having spoken to him mere minutes ago.
Dubosky was later called back to Vandenberg Air Force Base to speak to Leonard Song who believed he had found a way to assume remote control of Rom's armor.