Most fighters are mighty combatants on the physical level, their skill with a blade propelling them forward against all opposition. However, there are a few who have chosen not to master the weapon, but the art of war itself. Generals of endless armies, admirals of pirate kingdoms, hunters of wild tribes, wise philosophers. All are commanders. Commanders find themselves overseeing the vast conflicts of the world, some even drafted as generals in the endless blood war. Whether they were appointed by a king or sought power alone, their choices often dictate who lives and who dies. The burden of leadership is difficult, but those who rise to overcome those difficulties go down in history. All commanders are strategists, constantly seeking out advantages and disadvantages in combat.

Tactician

3rd and 10th level Commander feature

When you choose this archetype at 3rd level, you gain proficiency in Deception, Insight, and Investigation if you don't already have them. You also gain proficiency in one gaming set of your choice. 

At 10th level, your proficiency bonus is doubled for any ability check you make that uses any of these proficiencies. 

Command Techniques

3rd-level Commander feature

After studying strategies and operations on the battlefield, you have learned special techniques to tip the odds in favor of you and your allies. These techniques are fueled by Command Points. You have a number of these points equal to your proficiency bonus, and can use them in the following ways below.

All of these techniques expend the Command Point that they use, as specified in a techniques' description, and you can’t use a techniques if it requires you to use a point when your points are all expended. You regain all of your expended Command Points when you finish a short or long rest.

Interception: You impede the efforts of retreating enemies. You may use a bonus action to expend a command point. When you do so, choose up to 5 friendly creatures that can see or hear you. Until your next turn, if any of those creatures make an opportunity attack, they can make two melee attacks instead of one. In addition, creatures provoke opportunity attacks from the chosen group even if they take the Disengage action before leaving their reach.

Stimulus: You grant your allies a temporary boost in the battlefield. You may use a bonus action to expend a command point. When you do so, choose up to 5 friendly creatures that can see or hear you. They may immediately use their reactions to gain temporary hit points equal to your proficiency bonus + half your level.

Strategic Reposition: You maneuver your allies into more advantageous positions. You may use a bonus action to expend a command point. When you do so, choose up to 5 friendly creatures that can see or hear you. They may immediately use their reactions to move up to their speeds without provoking opportunity attacks. 

Take Cover: You warn an ally of the dangers around them. You may use a bonus action to expend a command point. When you do so, choose up to 5 friendly creatures that can see or hear you. They may immediately use their reactions to take the Dodge action.

Battle Planner

7th level Commander feature

Before combat starts, you can make a special check called a Command Check to determine possible outcomes and plan for the future. To make a Command Check, you must know who or what you will be fighting. You cannot make a command check against an unknown target. Making this check takes an hour and can be done during a short rest. For each additional hour and 50 gp that you spend making this check, there is a 20% chance of getting an additional +1 bonus your rolls. The check will remain affective for 7 days, until you make another check, or when the circumstances of battle change. 

It consists of three checks: Intelligence (Investigation), Wisdom (Insight), and Charisma (Deception), with a DC determined at random based on the quality of the opposition that you are opposing. A big part of the challenge in planning battles lies in knowing or not knowing your opponents, so your DM should base the difficulty of these checks on your knowledge the adversary, their knowledge of you, and the Intelligence, Wisdom, and Charisma scores of your adversary. Once you roll initiative, your DM will tell you the results of your check:

Command Check Results:

RESULT	VALUE
0 successes, failed by 3 or more	Your predictions were wrong. You and your companions have disadvantage on attack rolls for 1 minute.
0 successes	You were unable to achieve any advantages.
1 success	You managed to discover something interesting. You and your allies can't be surprised
2 successes	You were able to uncover more about your opponent's tactics. You and your allies can't be surprised, and your enemies can't get advantage on attack rolls for 1 minute
3 successes	You have predicted your enemy. You and your allies can't be surprised, and your enemies get disadvantage on attack rolls for 1 minute.
3 successes, succeeded by 3 or more	You perfectly molded the battlefield. You and your allies can't be surprised and have advantage on attack rolls for 1 minute. Your enemies get disadvantage on attack rolls for 1 minute

Tactician

3rd and 10th level Commander feature

When you choose this archetype at 3rd level, you gain proficiency in Deception, Insight, and Investigation if you don't already have them. You also gain proficiency in one gaming set of your choice. 

At 10th level, your proficiency bonus is doubled for any ability check you make that uses any of these proficiencies. 

Vigilant Leader

15th level Commander feature

Starting 15th level, when you roll initiative and have no command points remaining, you regain one command point. In addition, your allies no longer need to use their reactions to gain the effects of your techniques and your techniques can affect any number of creatures as long as they can see or hear you.

The Art of War

18th level Commander feature

You have achieved complete supremacy over the battlefield, and can perform more complicated strategies.You may use an action to expend three command points. When you do so, choose up to 3 friendly creatures that can see or hear you. They may immediately take the Ready action.