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Bear Threat
Lacerate vs. Pulverize threatwise

Basically, Mangle is huge. Around 5000 threat (or double that if it crits). It should be kept on cooldown on boss fights or when you need to smack something really hard to make it pay attention to you.

Fury Swipes is a close 2nd place in terms of threat and is a proc off of your auto-attack. Make sure you take 3/3 in the Fury Swipes talent. It hits for about 85% of Mangle's threat, but you have no control over it except to auto-attack whatever you want threat on.

Pulverize isn't bad, but isn't great either and it consumes Lacerate off of the target. Use Pulverize to keep your +9% crit buff up, then put three stacks of Lacerate back up on the mob over the next 5 GCDs so you can refresh Pulverize again. Threat is about 40% of a Mangle.

Maul is about equal to basic melee auto-attack. Which generate about 25-30% of what Mangle does, but Maul doesn't use up a GCD so it can be added on top of Mangle (if you have enough rage). Use your clear casting procs for Maul if possible.

Lacerate is another strong single-target threat at about 20% of a Mangle. The advantage is that it makes a great GCD filler for when Maul/Mangle are on cooldown or you want to build threat without using the expensive Maul. Sprinkle Lacerate around liberally along with Maul on multi-mob packs. The main threat is in the application of Lacerate and not the DoT effect. The primary reason to keep Lacerate up is for free Mangle procs, not for threat. So feel free to clip Lacerate DoTs and constantly re-apply it to mobs.

Faerie Fire (Feral) is only so-so. Use it as a pulling spell, but after that it's better to use Lacerate. I now save FFF for use on mobs that have stayed out of melee range. If I put FFF on them in the 60s/70s levels, I can keep the mob off the healer without having to growl at it or go chase it down right away. That may or may not work at 85.

Swipe and Thrash are AoE tools. Use both if you have them on multi-mob (3+ mobs) packs.

Summary:

Mangle = huge threat
Fury Swipes = random proc off auto-attack, about 85% of a Mangle
Pulverize = 40% of a Mangle
Maul = 25-30% of a mangle on the primary, half that on the secondary (if glyphed)
Lacerate (application) = 20% of a Mangle, the dot ticks don't do much threat
FFF = 10-15% of a Mangle