AoE or Single mob tanking? Follow

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Truncated info (you need to read all that if you want to tank):

Blood- Single Target (basically bosses).
Frost- Balanced between single and multi.
Unholy- Multi-target.

You can still use Unholy for bosses, though.

And, imo, Blood's AoE < Unholy's ST. Though the BB changes, and the ability for Blood to get UB, helped them a lot.

Sample Builds (That I just quickly made up and are far from the best):
ST Blood
Multi Frost
Multi Unholy

You can use these as guidelines for creating your own, but I don't recommend just using them. As a tank, it is best if you truly understand your tree. You want to know where your threat is coming from and where you can expect it, so you can remedy places that will have holes. You also need to think about the kind of mitigation you have.

The Blood one is Single-Target. A multi-target build probably needs to pick up 3/3 Morbidity, though you may be able to skip it if you go deeper and grab UB. But, if you do that, you'll need to grab some APen on gear. An AoE build may benefit from MoB quite a bit, too. You know, in organized situations, which mob will be last to die. Slap MoB on him and watch as the trash heals you for 4% of your max health each hit.

Both those Frost and Unholy builds are fine in ST and AoE situations, though the glyphs aren't exactly maximized for both. HB, for instance, won't help ST other than Rime procs. UB is debatable. 30 seconds of passive threat, even to one target, is still really nice (and it can tick for 300 threat per w/ FP, so it isn't bad). SS has a chance to reset diseases. So, if the RNG doesn't hate you, it can lead to a nice addition in Threat. Bone Shield is required. It will last, with 6 bones, a minimum of 21 seconds (so, in AoE situations). With high avoidance against bosses, you can get it way higher.

Yeah. But, read that link. Some of it is outdated, but still fairly relevant.