Shadowfiend Macro

[Vampir]

/script UIErrorsFrame:UnregisterEvent("UI_ERROR_MESSAGE");
/console Sound_EnableSFX 0
/use 13
/cast shadowfiend
/cast shadowcrawl
/script UIErrorsFrame:RegisterEvent("UI_ERROR_MESSAGE");
/console Sound_EnableSFX 1

I'm not 100% sure this will work if the shadowfiend has a global cooldown in it. From my tests it doesn't look like it does but you'll have to give it a try.

[Oonayah]

Worth mentioning that this is one of those macros you have to hit twice to make it work.

Worked great for me. Thanks, Vamp!