How can I solve this BootCamp partition mess I've created? This is my diskutil list. I've gotten my new iMac today and everything was going great so I wanted to install windows via bootcamp. After it booted into Windows setup I had problems choosing and formatting the BootCamp partition that was created, so I deleted it and chose new. After this didn't work either I restarted and after several different tries I now have this mess of partitions that I can`t delete via BootCamp Assistant nor Disk Utility. 

Does anyone have an idea how I can solve this so I can get to my original FusionDrive disk to try from the beginning?
Boot to Internet Recovery Mode
Open Terminal in the menubar > Utilities
Enter diskutil list to get the disk identifiers of your internal SSD (probably disk0), HDD (probably disk1) and the CoreStorage volume (probably disk3 or disk4 - apply the disk identifiers below according to the findings in your environment)
Now remove the seven partitions on the HDD with gpt:

diskutil umountDisk disk3 #the device identifier of the CoreStorage volume
diskutil umountDisk disk1 #the device identifier of the HDD
diskutil umountDisk disk0 #the device identifier of the SSD
gpt remove -i 9 disk1 #the device identifier of the HDD


Repeat the above steps six times but lower the index number (-i) by one in each step:

diskutil umountDisk disk3 #the device identifier of the CoreStorage volume
diskutil umountDisk disk1 #the device identifier of the HDD
diskutil umountDisk disk0 #the device identifier of the SSD
gpt remove -i 8 disk1 #the device identifier of the HDD


...

diskutil umountDisk disk3 #the device identifier of the CoreStorage volume
diskutil umountDisk disk1 #the device identifier of the HDD
diskutil umountDisk disk0 #the device identifier of the SSD
gpt remove -i 3 disk1 #the device identifier of the HDD

Resize the CoreStorage stack:

diskutil cs resizeStack lvUUID 2120g


with lvUUID: the UUID of your Logical Volume (8DC64131-3881-4971-B870-2FB6BFB58EDB)
Reboot to your main volume
Reinstall your current system to recreate your missing RecoveryHD or use this tool Recovery Partition Creator




Instead it should also be possible to merge all partitions (disk1s3-disk1s9) to free space and expand the CS LV then without booting to Internet Recovery Mode (untested):

diskutil mergePartitions Free Space disk1s3 disk1s9


Then reinstall your current system to recreate your missing RecoveryHD or use this tool Recovery Partition Creator