File:IllidanBCart.jpg

Summary
Illidan Stormrage standing before the Dark Portal, by Wei Wang, 2005.

This image appears on page 108 of The Art of Blizzard Entertainment. Its caption reads: CHRIS M.: Wei's first Illidan image.

SAMWISE: That's more purple than.

NICK: I thought it was cool that it was showing the shadow side of him versus the lit side.

Source
Wei Wang's ArtStation:
 * Web page
 * File link