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On Payload maps, the BLU team must escort a cart full of explosives through a series of checkpoints and into the RED team's base within a certain amount of time. BLU team members move or "push" the cart by standing next to it - the more people near the cart, the faster it moves. Any RED team member standing near the cart will stop it from venturing further. If a BLU player does not push the cart after 30 seconds have passed, the cart will start slowly moving backwards until it reaches a checkpoint/BLU spawn or a BLU player stands next to it again. The cart works as a Level 1 Dispenser for the BLU team (and disguised enemy Spies) to restore health and ammunition to those pushing it.
Payload maps may or may not be split into multiple rounds. Some maps traditionally have one-way routes from the BLU team's side, sometimes closed off until a specific point is taken.
Maps such as Gold Rush, Hoodoo, and Thunder Mountain are split into three stages that the BLU team must advance through and win. Stages one and two have two checkpoints and stage three has three checkpoints (two for Hoodoo), counting the final point as such. The Badwater Basin and Upward maps have a single round with four checkpoints, counting the final point as such. Advancing the cart to the next checkpoint gives the BLU team extra time. Advancing it to the final point moves the map onto the next stage. When the cart reaches the final point on the final stage, the Payload cart will explode killing anyone standing too close to it and destroying the RED team's base as well, thus symbolizing the BLU team's victory.
Unlike Standard Payload maps, Payload Race maps feature both the RED and BLU teams issued with a cart, therefore teams are not defined to an attacking or defending role. To win, each team must simultaneously push their cart through enemy territory to reach the finishing point while preventing the enemy team from doing the same. As with Payload maps, team members push the cart by standing next to it, with more members increasing the speed of the cart and any opposing team member standing near the cart stopping it. Also like Payload, each cart works as a Level 1 Dispenser for their team (and disguised enemy Spies), restoring health and ammunition to those pushing the cart.
Unlike Payload maps, the cart will not move backwards after any duration of time and there is no time limit; the map will only end when one team successfully pushes their cart to the finish point. Parts of the track may feature slopes or other obstacles on which the cart will quickly roll back down to the bottom unless being constantly pushed. Sections of the track that can do this will have chevrons on the progress bar to help show how far the cart must be pushed to overcome them.
Payload Race maps are either single- or multi-stage. Pipeline and Nightfall are split into three stages, whereas Hightower consists of only one stage. Winning in each of the first two stages will give an advantage to the winning team in the next stage (the cart is pushed slightly forward from the starting point).
Payload maps carry the pl_ prefix; community maps are identified with an italic font.
Payload Race maps carry the plr_ prefix; Community maps are identified with an italic font.
Carts are the objective and focus of the Payload and Payload Race game modes.
Carts are attached to a line of railroad tracks; the objective being to push the cart along said tracks while the enemy team attempts to stop it. The cart is pushed by standing next to it – the more people, the faster it moves (up to a maximum of three – see Speeds section below). If any opposing team member gets near the cart, it is blocked and the cart will not move until all opposition is removed. If any buildings get in its way, the building is destroyed as the cart runs into it. The cart acts as a Level 1 Dispenser for the team that owns it by restoring health and providing ammo and metal. Unlike Level 1 Dispensers, the cart does not have a limit to the amount of metal it can give to Engineers. It will also provide ammo and health to Spies disguised as its team.
If a cart is left unattended on specifically marked slopes, it will naturally roll down backwards. The cart-pushing team must push it continuously to get it up such hills, whereas reaching an inclined slope becomes a sort of checkpoint that the cart cannot reverse past. As of the Engineer Update, the cart has a glowing, team-colored outline effect that enables its position to be identified through walls and from further away, allowing players to keep an eye on its whereabouts at all times.
In Payload mode, the BLU team must push a cart through a series of checkpoints and into the RED team's base within a certain amount of time. Reaching a checkpoint adds time to the timer. If a BLU player does not push the cart after 30 seconds have passed, the cart will start slowly moving backwards until it reaches a checkpoint/BLU spawn or a BLU player stands next to it again. If the cart is not moving backwards when time runs out Overtime will occur, which gives the attacking team five seconds to move the bomb or they lose. The timer resets each time the cart is touched.
In Payload Race mode, both teams are issued a cart. The teams must simultaneously push their cart through enemy territory while preventing the enemy team from doing the same. Unlike Payload maps, the cart will not move backwards after any length of time (unless it is on an inclined slope) and there is no time limit; the map only ends when one team successfully pushes their cart to the finish point. Payload Race maps tend to use rolling slopes much more than standard Payload maps. During Overtime, both carts will automatically move forward slowly to prevent Stalemates. Pushing one cart stops the other from moving forward by itself.
Lil' Chew Chew
On the Payload map Frontier, a substantially larger mechanized train engine known as Lil' Chew-Chew is used in place of the standard BLU cart. Providing cover from frontal attacks, the Train is capable of significantly damaging anyone who finds themselves (whether willingly or forcibly) in its mouth when it is moving forwards; the damage done increases as more players ride its rear platform to the point where three or more attackers cause it to deal an instant-kill. The platform also has a built-in BLU Dispenser, however, those riding on it will have trouble seeing directly in front of the cart as the main body of the train is in the way. It has a noticeably increased pushing range when compared to normal carts.
The cart speed depends on the amount of people (the multiplier) that are pushing. Currently, all Standard Payload maps use the same speeds. Speeds are measured in Hammer units per second. Note that the capture limit is 3 players, and any additional players who push it will not increase the speed further.
The BLU team's bomb cart.
The special model for the cart on Hoodoo.
The following models are present in the game files, however, remain unused.
- Added Payload mode.
- Added map: Gold Rush.
- Added map: Badwater Basin.
- Added proper handling of cart blocking recognition to Payload maps
- Added maps: Hoodoo and Pipeline.
- Added maps: Hightower, Thunder Mountain, and Upward.
- Added maps: Frontier and Nightfall.
- Added map: Barnblitz.
- [Undocumented] Payload carts no longer maintain player overheal.
- Added Enabled/Disabled inputs for the mapobj_cart_dispenser entity.
- Fixed cases where the Payload HUD looked like the cart is still on a hill when it isn't.
- Fixed exploit where players could be pushed into enemy spawn rooms by the Payload cart.
- The cart may sometimes randomly spin vertically.
- The capture progress HUD sometimes does not report how many players are pushing the cart. It may also display the cart as being blocked when it is not.
- Dying due to the cart explosion causes the Deathcam to focus on a specific point of the map while displaying the name of an opponent, even if no enemy was involved in the player's death.
- It is possible to derail the cart as it is falling by launching it with an explosion. This works because it becomes a physics prop when it reaches the end of the track.
- A very rare glitch occurs when the doors to BLU will not open, and the map will stay in Setup Time. The cart will slowly push itself and cannot be blocked.
- The default Payload takes the shape of a "Fat Man" implosion-style plutonium atomic bomb. This type of bomb was dropped over Nagasaki during World War II.
- Originally, an Engineer could upgrade the Dispenser on the cart, allowing it to give increased healing, ammo, and metal. This has since been fixed.
- Hoodoo uses a different cart model. The map description reveals the cart to be carrying a "dirty bomb" – a nuclear explosive consisting of little more than radioactive material strapped to conventional explosives, such as TNT.
- On all of the carts, there is a Heavy quote written into the paintwork:
- The default cart bears the words 'Cry some more' scratched into the paintwork.
- The Hoodoo cart has the words 'So much blood!' painted in white on the front-most barrel and the word 'Bonk' written in dust underneath one of the straps (most likely by the Scout).
- Lil' Chew-Chew bears the words 'All of you are dead!' scratched into the paintwork in front of the smoke stack.
- The light on the Payload cart is the same as the one duct-taped on the Combat Mini-Sentry Gun.