The rocket with the capture platform on sd_doomsday.
Special Delivery
Special Delivery is a game mode introduced in the Pyromania Update. The objective for both teams is to take a neutral briefcase to a specified area of the map, while preventing the other team from doing so. It combines elements of Capture the Flag and Payload.
Once the round starts, the neutral Australium briefcase is unobtainable for 45 seconds. Once taken by a member of a team, the Australium becomes property of that team by switching to that team's color and will emit gold sparkles, small clothing particles and a long golden trail. If the carrier is killed, the briefcase will be dropped and can only be picked up by the same team. If the opposing team successfully defends it for a duration of 45 seconds, it will return to its original location and become neutral again, allowing either team to take it.
Gameplay
Players must take the Australium to a loading platform. Only the team with the Australium can make the platform operate. Similar to the Payload Cart, the platform will gradually dispense health and ammo to friendly players. Unlike the Payload Cart, the speed of the loading platform is not dependent on the number of teammates on it; only the teammate carrying the Australium can move the platform. If the Australium is dropped or the Australium leaves the platform, the platform will retreat and gradually return to its original position.
Once the platform reaches the top of the rocket, a compartment on the nose of the rocket will open. The team that places the Australium in this compartment will launch the rocket, winning the game. Note that once the Australium compartment is open, the platform no longer needs to be raised in order to launch the rocket. As long as a player is able to make contact with the compartment, the rocket will launch.