What is an Acronis Survival Kit?
To recover your Mac in case of a failure, you need to have two crucial components—a backup of your system disk and a bootable media. Most often these components are separated, for example, the system backup is stored on an external drive or Acronis Cloud and the bootable media is a small USB flash drive. Acronis Survival Kit combines both components so that you could have a single device that has everything that you need to recover your computer in case of a failure. It is an external hard drive that contains both the Acronis bootable media files and a backup of your system partition or entire computer.
As a device for an Acronis Survival Kit you can use an external hard drive that is larger than 32 GB and has Mac OS Extended or APFS file system. If the drive has another file system, Acronis True Image 2021 suggests formatting the drive.
Fusion Drive is not supported as target for Acronis bootable media and Acronis Survival Kit.
How do I create an Acronis Survival Kit?
When you configure a local backup of your system or entire Mac and select an external drive as a destination, Acronis True Image 2021 will suggest making this drive bootable.

To create an Acronis Survival Kit:
Acronis True Image 2021 creates a small partition on the selected drive and writes the boot files there. To create it, one of the existing volumes will be resized. If the disk is not a GPT one and has a file system different from Mac OS Extended or APFS, Acronis True Image 2021 suggests formatting the disk. Pay attention, that disk formatting deletes all the data stored on the disk.
When your Acronis Survival Kit is ready, you can use it to recover your Mac. Refer to Recovering your Mac for details.