No they do not share a cooldown, and any rogue who is losing in an arena and doesn't try to vanish to regain some semblance of balance needs to L2P.
The only time I don't Vanish in arena is if I have a bleed on me and I know it's not going to work. Even then I'll sometimes try to time the vanish right after a bleed tick to get 2-3 seconds of stealth time and maybe get a cheap shot off.
Cloak of Shadows is an almost necessary skill to use when fighting a warlock, mage, or shadow priest. Wait until they have all of their DOTs stacked, hit Cloak of Shadows and voila, all the dots go away, they can't apply any more to you for 5 seconds, and they most likely can't root/fear yiou for 5 seconds as well.
There's a reason people call Cloak of Shadows "Cloak of Skill" and "Cloak of Warlock Killing".
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Sir Xsarus wrote:
That's pretty much the best ninja edit ever.
World of Warcraft
Aggramar Alliance
Allizsah: 92 Human Paladin