These may have their reels aligned in an irregular fashion, as opposed to standard rectangular grid, or they may even feature reels and rows that rearrange themselves throughout the game.
https://talkingpoints.org/subx/showthread.php?tid=91296
https://www.ww2.site/forum/viewtopic.php?t=286436
http://forexam.ru/component/kunena/?func=view&catid=5&id=162850#162850
https://muchroom.ng/index.php?topic=117152.new#new
https://planeswalkers.org/viewtopic.php?t=34424
https://forum.zweb-apps.xyz/viewtopic.php?t=188987
http://www.lada-xray.net/showthread.php?p=241923#post241923
https://www.ww2.site/forum/viewtopic.php?t=93152
https://catrachosporelmundo.com/index.php?topic=813.new#new
http://60.250.226.63/ipkb/viewtopic.php?f=41&t=1965771
https://catrachosporelmundo.com/index.php?topic=25646.new#new
http://www.horsecity.ru/phpBB3/viewtopic.php?f=10&t=222838
http://www.lada-xray.net/showthread.php?p=220564#post220564