"The Last Stand, Four of Four"
The world has been attacked by The Coil. GI Joe, assisted by the USS Flagg led by Keel Haul, is in a full on invasion of the Coil stronghold on Cobra Island, and Cobra has added its presence to the mix. The small Joe force that has escaped from the command center connects with the main force. A fight between Cobra Commander and Serpentor ends with Serpentor falling off a balcony into a lake at the bottom of a waterfall. Cobra Commander escapes on a submarine, and the child clones of Serpentor are recaptured. Several Joes die.
Spoilers: GI Joe deaths include Flash, Mainframe, Skidmark, and Chuckles.