I am most likely rerolling of my ret of 7 years to Unholy DK. We'll see, but so far I like it a lot. I find ret terribly boring for mythic since a few support abilities were changed/removed, so I may as well just go full DPS at this point.
Runic Corruption is cool, but I'd like to actually micro the Blood Tap so I can get maximum performance. When exactly however do you use Blood Tap? Do you go through your rotation and use Blood Tap when you can't do anything anymore, do you use it on CD regardless of its # of stacks? When you use it, do you also mash it to consume all of the stacks, or do you only use a certain amount? It's confusing to a new DPS DK.