This guide will focus on obtaining the following achievements:
- House Party of the Dead
- Team Sonic

What do you need to get the achievements:
- 1 Gaming Controller*
- 2 or more friends on steam with the game (only for the "Team Sonic" achievement)

* Other Plug-&-Play devices might work, though you would have to experiment

Before we do anything, it's recommend to wipe your currently setup controller configuration.
Go to "My Documents", and open the "SART" folder.
Location: C:\Users\YOURNAME\Documents\SART

In this folder, you will find the file "controllers.txt", delete this.
If the file isn't there, ignore this step.

Next, run "Sonic & All-Stars Racing Transformed" through steam.
You will now get 2 options to choose from.
Choose for the option "Configure"

Now you will be in the configuration menu.
In this menu click on the blue button: "Controls"
Click on "Select Controller" for Player 1.
In this menu you can see all the devices that are hooked up to your computer.
Select your controller.
Once you choose your controller, click on "OK" and afterwards again on "OK" followed by "Quit"

Now that your new "controllers.txt" has been generated, open this text document.
(you can drag the document in notepad)

The second line in this document says: "<num_devices>1</num_devices>"
Change the number 1 into a 4.

Under "menuController_0" on line 4 there is a line called "<menuDevice_instance>...".
Copy the whole line and paste under "menuController_1", "menuController_2" and "menuController_3".

As for the last step, copy everything between "<vgp_0>...</vgp_0>" and paste it between "<vgp_1>...</vgp_1>", "<vgp_2>...</vgp_2>" & "<vgp_3>...</vgp_3>"

Run "Sonic & All-Stars Racing Transformed" through steam and get to the main menu.
If done correctly, the 3 player icons below will be flashing, confirming that they are listening.
Press Start and all the other 3 players will join under the same controller.

Document EXAMPLE:

Recommended Map: Ocean View
Recommended Difficulty: Expert/Hard

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Run the game and press "Start" to get the other 3 players.
Go to "CAREER" followed by "WORLD TOUR".
Choose Hard/Expert as difficulty (any difficulty will do but export mode will go the fastest)
When you are in the "Character Select" screen, Select "RANDOM".

Once the race starts do nothing, the CPU will do its laps and eventually reach the finish.
Once the first CPU finishes, a countdown timer will start and once it hits 0, the race will be over.

Afterwards you will be rewarded with the "House Party of the Dead" achievement.

Recommended Map: Shibuya Downtown
Recommended Difficulty: Expert/Hard

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Run the game and press "Start" to get the other 3 players.
Go to "CUSTOM GAME" followed by "ONLINE".
Choose Hard/Expert as difficulty (any difficulty will do but export mode will go the fastest)
When you are in the "Character Select" screen, Select "RANDOM".
Have 2 or more friends join you online to fill up your join list so you can start the game.


Once the race starts, have your friends do nothing, you will be the only one to hold down gas in order to have your 4 drivers go forward.
As this stage (Shibuya Downtown) is curved and has no real obstacles, it will get you to the finish if you only hold down the gas paddle, you can steer a little to get your drivers more properly aimed if they are hugging the wall too much.
It does NOT matter how you finish, as long as your 4 drivers finish in the top 4.

Afterwards you will be rewarded with the "Team Sonic" achievement.