Warrior 30-Minute Cooldowns

Retaliation

Battle Stance - Free
Max Rank Tooltip: Instantly counterattack any enemy that strikes you in melee for 15 sec. Melee attacks made from behind cannot be counterattacked. A maximum of 30 attacks will cause Retaliation.
Talent References: Improved Discipline

Description: Retaliation is the first 30-minute cooldown ability you'll receive, and it causes you to automatically counterattack (read as; weapon swing) any frontal attacks. However, it should be noted that it does NOT work on any attacks that come from behind you or if you're otherwise incapacitated (stuns). It's an interesting ability, and it has some nice utility in AoE situations (Challenging Shout + Retaliation = Big numbers!). It largely gets replaced by Recklessness in terms of damage output, though, once you've acquired that ability... and this ability is not even really useful in PvP due to the addition of the huge, incredibly noticeable "don't hit me!" circle of daggers that shows up when you use the ability.

Shield Wall

Defensive Stance - Free
Max Rank Tooltip: Reduces the damage taken from melee attacks, ranged attacks and spells by 75% for 10 sec.
Talent References: Improved Discipline, Improved Shield Wall

Description: Shield Wall is one of the best Warrior abilities, and it's fairly obvious why once you look at the ability. Shield Wall is a tremendous tanking asset, causing you to take extremely limited amounts of damage and giving your healers a break/letting you live through massive amounts of burst damage. It's handy as hell in PvP as well if you're attempting to defend one area (such as an Arathi Basin flag) by letting you live through pretty much anything that's sent your way, even when massively outnumbered, for the duration of the ability.

Recklessness

Berserker Stance - Free
Max Rank Tooltip: The warrior will cause critical hits with most attacks and will be immune to Fear effects for the next 15 sec, but all damage taken is increased by 20%.
Talent References: Improved Discipline

Description: Recklessness is crazy. It will leave you with a nearly (or actual) 100% Critical Strike rate, making you immune to Fear effects for the duration, albeit also increasing your incoming damage by 20%. A very handy move, as it allows you to take on Elite mobs that may otherwise be FAR too difficult for you to kill alone through the application of massive burst damage, as well as letting you obliterate opponents in PvP. The infamous Recklessness Execute bomb is a common feature of most raid PvE situations as well, letting you output massive amounts of damage to finish off a boss by spamming critical executes.