There are few artists who use this name:

1) Ill is a progressive metal/math metal/thall band from Kazan, Russia. https://vk.com/illband • https://illband.bandcamp.com/

2) Nakako (Koji Nakamura) is the ex-singer of the Japanese experimental pop/rock/electronica band Supercar. After the breakup of Supercar, he went on to work on various other projects including Nyantora and iLL. With iLL, he has also worked with contemporary Japanese artist Naohiro Ukawa.

3) ill is a hard rock band from Atlanta, Georgia that plays a heavy blend of rock, blues, industrial, and punk. ill released the album Down In Deep in 2009, and released a self-titled EP in 2010.

4) A hardcore punk band from Sydney, Australia. Now known as Ill Brigade

5) A french underground rapper, ex-member of the band X-Men.

6) A Nu-Metal band from Sweden.

7) Hardcore/punk band from Warsaw

8) A post-punk band from Manchester.

9) American rapper, also known as Illecism also known as Xuice Hades.

10) A Psychedelic Black Metal from Limbourg, Belgium: http://illpsychedelia.bandcamp.com/releases
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