This guide will cover supplemental information for Arms Warrior in Legion. Bear in mind that as the meta develops in the early stages of the season, you can expect to see some changes to the following information. All information in this guide has been provided by Joefernandes (Blizzcon Champion, 9x Rank 1, 12x Gladiator).
Your talent choice for your first tier of talents will highly depend on what comp you are fighting against and what other talents you will be selecting. In situations in which are are likely going to be dealing single target damage, Overpower is the best target. That being said, Sweeping Strikes is incredibly effective against double melee teams, especially if they are constantly stacked on top of one another. As of 7.1.5, Sharpened Blade is one of the primary talent choices later on. The improved Mortal Strike effect from this talent can be spread with Sweeping Strikes, making it incredibly effective against stacked targets. The third talent on this tier, Dauntless, can be played if you are wanting to deal as much spread pressure as possible. You should select this talent if you plan on playing with Rend, Titanic Might, Mortal Combo, and Opportunity Strikes.
Your talent choice for this tier really depends on the comp you are playing against and how many stuns are available for your team. Storm Bolt and Shockwave are the two talent options on this tier. Storm Bolt is good against non-melee cleave teams in which your primary focus is controlling one target. This works really well if you are playing a comp like Warrior/Mage and need to have a controlled stun for enemy healers. Against melee cleaves, or against teams in which you can almost guarantee to stun more than 2 people, Shockwave is a better option as you might need it to control multiple targets. There aren’t many situations in which you would want to play Double Time. The only time you would ever play this talent is if there are multiple stun DRs available for your team and you instead need additional mobility against slippery targets.
Cooldown stacking has always been really powerful as a Warrior. Because of how important burst damage is in Legion, Avatar is the best talent on this tier. When stacked with Battle Cry this can lead to a lot of damage. Alternatively you can play with Rend if you want to focus on dealing AoE damage.
Defensive Stance is the strongest talent on this tier. This ability represents a pretty powerful defensive CD without that much of a damage loss. You will likely rely on this ability quite often to deal with enemy CDs or to survive when your healer is crowd controlled.
As of 7.2, Mortal Combo is the optimal talent for your fifth tier. This allows you to keep a Mortal Strike debuff on one or more targets, which will give you better pressure in both single target and AoE damage scenarios. You can still play Focused Rage if you want as much burst as possible. This is sometimes useful in comps like Turbo Cleave where you will be dumping a lot of damage during small intervals (usually with Bloodlust).
Unless you are wanting a burst damage oriented build (with Focused Rage) then Titanic Might is the optimal talent on this tier. This talent gives you more consistent damage and can be utilized to potentially keep Colossus Smash on two targets, allowing you to deal increased AoE damage. If you are playing a burst damage oriented build, then Deadly Calm is a powerful alternative talent as it guarantees that you are able to get off meaningful damage during the duration of your Battle Cry.
Unless you are playing a Focused Rage build, Opportunity Strikes is the best talent on this tier. Overall this talent offers extremely consistent damage and works really well in comps where you want to deal AoE damage. If you are playing Focused Rage, you should definitely play with Anger Management. Because Focused Rage acts as a rage dump, you will be able to benefit often from this talent.
As a Warrior, your primary goal is to deal as much damage and be as disruptive as possible. Doing so requires to have the highest possible uptime on enemy targets. Because of this, Relentless is the best talent on your first tier if the enemy team has lots of CC effects. I might chose Relentless against Mage and Sub Rogue teams where I am likely not going to be the kill target. If the other team has limited CC effects and will CC you infrequently, then Adaptation is the strongest option. This is especially true as a Human Warrior because you will have an additional CC break through your Human racial. Alternatively, if you think you will need to have a controlled CC break in a matchup, then play with Gladiator’s Medallion.
Reinforced Armor is the best talent if the enemy team has at least one caster DPS. If the enemy team has two melee DPS, then play with Sparring as it represents a decent amount of physical damage mitigation. Lastly, Hardiness is a viable option against teams that try and execute 100-0 deaths on you, such as RMD.
One of the most frustrating things as a Warrior is not being able to execute your target due to it being out of range. Death Sentence is the perfect solution for this problem as it gives your Execute a 15-yard range. This is really important for finishing off targets at low HP. Alternatively you can play with Disarm against any team with a melee DPS where you need additional control. This talent works really well when paired with Duel for keeping your teammates alive. You can also play Disarm against Holy Paladins to counter their melee wings.
Against any team with a caster DPS, I highly recommend playing with Spell Reflection. The utility this talent provides is simply too good to pass up. If the other team does not have a spellcaster, Rage Machine is my suggested alternative. Finally, you could play Master and Command against teams like WW/DK if your team is finding it difficult to survive damage.
Because the talent is no longer bugged, Duel is by far the best talent choice on this tier against any comp. This talent gives your team a powerful defensive option to utilize while under pressure. The only time you would want to consider changing this talent is if the enemy team will train you the entire game (which is incredibly unlikely).
As of 7.2, Sharpened Blade is the best talent choice for this tier. The increased MS effect is simply too powerful in this high damage, low healing meta.