As I have discussed before, all raiders should ensure that they have fully enchanted their gear in order to maximize their entire group's chance of success.  No one wants to be the cause of a 1% wipe because they couldn't be bothered to spend a bit of gold, right?  If this is good advice for DPS classes, then it is doubly so for tanks - hard-hitting bosses can stress out even the best healing groups, so why not ensure that we are innately as durable as possible.


Methodology
This guide will be broken down by gear slot, with my preferred selections for Bear-only, Cat-only, and hybrid (i.e. used in multiple sets) gear laid out.  Alternative enchantments will be listed separately.  Also, note that enchantments that are only available to people with certain professions have been excluded from this list - I see no need to tease ferals who don't have access to these perks, and generally they are best-of-slot any how, so don't really require being explicitly mentioned.

Head
Bear: Arcanum of the Stalwart Protector (+37 stamina, +20 defense rating)
Cat: Arcanum of Torment (+50 attack power, +20 critical strike)
Hybrid: Nothing really.  Pick either bear or cat depending on what your primary role is.

Other Options: 
Until you're revered with your faction of choice, any of the resistance enchants from the WotLK factions (e.g. Arcanum of the Fleeting Shadows) of the TBC Arcanum of the Defender  are decent stand-in for your bear hat, while the old Arcanum of Ferocity from TBC will keep your cat happy.

Shoulders
Bear: Greater Inscription of the Pinnacle (+20 dodge rating, +15 defense rating)
Cat: Greater Inscription of the Axe (+40 attack power, +15 critical strike rating)
Hybrid: Again - pick one based on your primary role.

Other Options:
Obviously the Lesser Inscriptions of the Pinnacle and Lesser Inscripton of the Axe are suitable stand-ins until you grind out exalted with the Sons of Hodir.  If you're feeling particularly feeble in the health department, the Heavy Borean Armor Kit could also be considered.

Back
Bear: Major Agility (+22 Agility)
Cat: Major Agility (+22 Agility)
Hybrid: Major Agility (+22 Agility)

Other Options:
Mighty Armor looks good on paper for a tanking cloak, but I think that the agility enchantment still beats it out.  Dodge and Titanweave are also out there, but Agility truly does beat them paws down.  Greater Speed exists for kitties, but haste isn't all that hot if you're a cat.

Chest
Bear: Powerful Stats (+10 all stats)
Cat: Powerful Stats (+10 all stats)
Hybrid: Powerful Stats (+10 all stats)

Other Options:
If you can't afford Powerful stats just yet, Super Stats is still fairly snazzy, and better than the other options out there.  If you're looking for a pure health boost, pick up a Heavy Borean Armor Kit instead of the Super Health enchantment - bear health scaling being what it is, you get more bang for far less buck.  Finally, if you're feeling like a rebel, strap on Greater Defense - it's not all that great though.

Wrist
Bear:  Major Stamina (+40 stamina)
Cat: Greater Assault (+50 attack power)
Hybrid: Expertise (+15 expertise rating) (Greater Stats if expertise capped)

Other Options:
For tanking gear, Greater Stats gives a modest increase to all stats, while Major Defense can be applied for a modest avoidance bump.    Cats could consider Brawn, although it would be sub-optimal.

Hands
Bear: Major Agility (+20 Agility)
Cat: Precision (+20 hit rating) (Crusher if hit capped)
Hybrid: Major Agility (+20 Agility)

Other Options:
Like the cloak armor enchantment, Glove Reinforcements looks pretty but doesn't appear to be the proper choice for bears.  likewise, Heavy Borean Armor Kit comes up short of the agility buff, and should only be used if your health is a huge problem area.   Expertise, Major Agility, and Major Strength are all dps glove alternatives.

Legs
Bear: Frosthide Leg Armor (+22 agility, +55 stamina)
Cat: Icescale Leg Armor(+75 attack power, +22 critical strike)
Hybrid: Frosthide Leg Armor (+22 agility, +55 stamina)

Other Options:
If you're not made of money, Jormungar Leg Armor (bear) and Nerubian Leg Armor (cat) are cheap alternatives to the best-of-slot gear.   Honestly, nothing else even compares to these.

Feet
Bear: Tuskarr's Vitality (+15 stamina, +8% run speed)
Cat: Icewalker (+12 critical strike, +12 hit rating) (Greater Assault if hit capped)
Hybrid: Superior Agility (+16 agility)

Other Options:
Greater Fortitude offers more stamina than Tuskarr's, but without the run speed - personally I believe that the speed boost is worth the small loss.  

Weapon
Bear: Major Agility (+35 agility)
Cat: Massacre (+110 attack power)
Hybrid: Major Agility (+35 agility)

Other Options:
Depending on its proc-rate, Mongoose can be better than Major Agility for tanking bears.  Cats can also consider Berserking (if they switch weapons when going to bear form to emergency-tank), or Accuracy (if you really need the +hit rating).

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