So I love that Cuore is the fairy godmother/self-appointed-moderator/custodian of the request section (depending on how you view the request section) but I love even more when I see him (although could be her?) branch out and view it as either an opportunity to something else, or maybe it's just part of his/her learning process (skins/skinning, like, lol wut?).
Anyways, I think I can help without even ever having seen a pic of Illidan all scarred up.
Let's see:
We know Illidan is a nightelf so he had purple-skin and green blood.
Which meant the scars looked light grey and maybe had a green tint due to blood (or else it would be purpley-blue (forgot the color) if his skin was magenta (NE skin is usually purple in games/3d but magenta when drawn in 2D)).
But because he actually has ashen grey skin, because demon's blood or whatever, his blood now is just really really dark (but not black).
But in Northrend, he would take on a colorscheme similar to your avatar which means his blood is a dark blue and his scars are then either:
1. Light blue(er)
2. Pale pink with dark blueish tint
3. Dark blue scabs on medium grey
Or else 4. - Dark blue blood clots
Which, of course, depends on how you want to depict how long ago it had been since he got the wound.
Unless you wanted to base it off exactly how it is in the video posted above, which would be something else. Although, it's pretty much the same thing just with deep purple blood instead of blue.
EDIT: I think I was basing it off of WoW appearance or of him drawn. I didn't realize that cutscene is wc3. His blood is obviously purple so then, because Deepstraz said 'cauterized' I'd personally probably go for 2. -a pale pink scar that's a little dark purple in the middle (same shade as his tattoos) .
EDIT EDIT: btw if it isn't obvious - I'm totally talking out of my ass here guys xD
