I don't know the Warlock class as well as I should - what should I be keeping an eye open for so I can get ready to play defensive/LoS insane demo burst? Last night both my healer and I got hit for a 207k chaos wave, followed by a 100k chaos wave..... ouch.
This isn't a whine thread btw - other classes can burst hard, it's just that I know what to look for when they do it and lock burst still kinda takes me by surprise.
when the warlock doesnt cast Hand of Guldan for a while (the purple meteor coming down from the sky) this usually means hes getting ready to pop cooldowns especially after 1-2 minutes into the fight as hes waiting to have 2 charges, when he goes in demon form and cast dark soul (you will notice a blue egg like effect on the warlock).
aslo if ur close enough to him to notice the horns on his head (purple horns when in caster form) this means he has 500+ fury and ready to burst.
edit: to clarify, red egg effect is for destro, blue effect is for demo