[Realme GT Master Edition] Turbine1991:
If anyone needs to downgrade (to root phone by patching boot.img with Magisk) or repair their bricked phone, this is how I did it. And please only do the root portion of this if you've already unlocked your bootloader. However downgrading will be fine as the package/boot has not been altered. Just make sure you use a USB cable with data, not one of those PD ones missing pins used just for charging.

-- Download firmware

(please DM me if the link dies, this has an Android 12 & 13 firmware, DO NOT upgrade to 14 as Realme made this update slow down our phones significantly and it adds other bugs)

https://mega.nz/folder/VAMmEQQa#CXcIuEesfdsd24RhUjb7PQ

-- Setup ADB/Fastboot commands

Download platform tools from

https://developer.android.com/tools/releases/platform-tools

Extract them into a folder, get the whole path and add it to the PATH environment variables. (search "environment" in the start menu to edit this)

-- Install Fixed USB Drivers

Then the USB drivers, I noticed the USB drivers didn't work for fastboot with our device (the driver didn't include our device id in fastboot mode) So download my modified usb drivers here, or search the internet with the unknown device's id when in fastboot mode and find how how to do it yourself.

https://drive.google.com/file/d/1KT_afZkxQS20lE-A3eAoqPMjRXLn_Rw9/view?usp=sharing

To install the usb driver, right click the inf and install. For the Qualcomm, just run the setup. Then reboot.

-- Obtain repairer key to flash firmware

Then I bought a realme OTP key from Aliexpress for GAProLogin. The tool can be downloaded from the official website. A tool like this often is identified as a virus, whether it is or not. I installed this on a dedicated laptop and disabled Windows defender using Windows defender uninstaller.

-- Flash firmware

I then opened GAProLogin, specify "other region" and the OTP key I purchased. Our model does not exist in the list, so we have to flash by firmware package. Add a new package, specify "other" as the model. Now find the firmware zip from HalabTech and extract to folder. Select this folder.

Now we need to boot our device into EDL mode (a mode used to recover Qualcomm devices). To do this, we can start the flashing with the device unplugged, turn off the device, plug it in and start the device. It will intercept the boot process and put it into EDL mode (screen will be blank, but the app will show progress)

Your device will now reboot.

-- Root

To root your device, connect your phone to the PC.

You may now connect the phone to your PC. You then need to copy the boot.img from the images directory in the firmware folder onto your phone, install the magisk apk from the magisk releases website, open the app and select an image to patch with magisk (boot.img), it will make the changes to a the file and be called something slightly different. Copy this modified boot image to your pc.

Now open a CMD window and browse to the path with the modified boot.img

To change directory: cd "C:\some path\here"

Now boot into fastboot mode, ensure phone is off. Hold volume down and hold the power button until the screen turns on, plug the phone into PC.

Write: fastboot flash boot boot_magisk_123.img

Now when it's done write: fastboot reboot

Once booted, search for the Magisk app and you'll see whether it worked.