Tactician

This fighter subclass is meant to incorporate more support to the team instead of only being a front-liner. Picking it means that you have trained your mind as well as your body so that, unlike the monk that converts wisdom into weapons, you use your wisdom to enhance your weapons.

You have trained your mind so much, in fact, that you are on par with some forms of divination magic. You gain a Tactical save DC and Tactical attack modifier. They are respectively:

Spell Save DC: 8 + proficiency bonus + wisdom modifier

Spell Attack Bonus: proficiency bonus + wisdom modifier

Cunning Mind

Thoughtful Leader

You know exactly what to say and when to say it. 

Deceptive Tactics

You gain expertise in deception and insight, regardless of previous proficiency.

Strategies

You and your team cooperate as one. Strategies allow your team to assemble into different shapes to serve different purposes in combat. At 3rd level, you get two strategies of your choice. At 7th level, you get two additional strategies, one strategy at level 10, and one final strategy at level 15. It takes one bonus action for you to initiate a strategy. You can use strategies as many times equal to your wisdom modifier in a long rest. You regain all your uses of strategies on a long rest.

Anatomical Strike-back

You have taught your team to aim for the weak points of the body. Aim for the jugular, kick the back of the knees, or punch the liver. While in melee range, as a reaction to being hit, you or your ally can attempt to hit the target in a key spot to disable it. Roll an unarmed strike attack. On a hit, the you or your ally make a second roll and the associated effect is placed on the opponent. See the list below:

1-10   -   The opponent was kicked in the legs and is knocked prone.

11-15   -   If the opponent hit you with a weapon, then their arm is disabled, forcing them to drop the weapon. If no weapon was used, the arm they hit you with is still disabled.

16-18   -   You severely damaged their armor (natural or otherwise), dropping their AC by 1. The AC returns to normal after a long rest.

19-20   -   You attacked an extremely vital organ or region, making them incapacitated completely. They recover after a long rest.

Bluffing

You become an expert at making you and your team seem more powerful than you truly are. You have backup, you are only using a tenth of your strength, your opponent has fallen into your trap. The art of the lie is yours to mold.

If an enemy in melee range attempts to attack any ally, or yourself, within 10 feet of you, either of you can use your reaction to impose disadvantage on the attack.

Clone Wall

Your enemy can't effectively attack your ally if they don't know which ally they are attacking. You and all of your allies within 5 feet of you immediately share materials and clothing to create similar and ambiguous disguises to conceal yourselves. The conditions of these disguises follow that of disguise self with your Tactical Save DC. While using this strategy, your enemies have disadvantage on attacks and saving throws, too confused to know who is who in  your party. When less than two of you remain completely disguised, the strategy ends.

Dog Piling

You and your allies work together to knock the opponent down and kiss the floor. You or your allies can attempt to grapple the opponent and knock them prone with advantage. If your opponent is already knocked prone while using this strategy, then any subsequent hit from an ally will deal an additional 1d6 bludgeoning damage.

Efficient Casting

In all your experiences with observing magic, you have picked up on ways to improve and speed up spell casting. For all allies within 30 ft of you, a spell's casting time is decreased. If it takes an action to cast, it becomes a bonus action. If it is a bonus action, it becomes a reaction. For numeric casting times, reduce the time by a factor of 2 (rounded down).

Fighting Dirty

Honor is not your strongest suite. And that is what has kept you alive. The way you suddenly attack throws your opponent off guard, disorienting their senses. On your or an ally's attack, hitting an opponent additionally allows one to inflict the conditions similar to blindness/deafness. Deafness can only be inflicted at melee range and does nothing if the creature is already deaf. Blindness however, does affect blind creatures even with true-sight, removing the ability. These conditions only last until the start of the next turn of the people who make these attacks. Additionally, making a creature deaf must be done in melee range.

Guerrilla Warfare

A confused enemy is a dead enemy. You and your allies attack the enemy and quickly retreat out of harm's way. While using this strategy, you and your allies have advantage on melee attacks and as a bonus action, you all can use the disengage action.

Guided Shooting

You take the lead in the heat of combat to distract your opponent. Meanwhile, you relay your foe's exact position, granting your ranged fighting companions the knowledge they need to make their shots. While using this strategy, ranged attacks have advantage. However, to keep your opponent focused on yourself, you cannot use the disengage action.

Raining Debris

The enemy can't seem to find his footing. The ground is your ally as you rain down trash and random objects. As a bonus action, you and your teammates can throw their possessions (of their choice) at enemies within 30 feet of any of you. The ground directly beneath the enemies becomes difficult terrain and they must make a dexterity saving throw against your Tactical Save DC. On a failure, they fall prone.

Resourceful Warrior

Mutual Failure

Even in failure against enemies, you find victory. If you are knocked prone and are within melee range, you can use your reaction to either knock your opponent prone as well or grapple them. You can still use this feature before being knocked unconscious or killed.

Weapon Improv Master

At 7th level, even a stick is a deadly weapon for your resourceful mind. You can use anything you are wearing or holding that isn't an established weapon. When you attack using a non-conventional weapon, add your wisdom modifier plus your proficiency bonus to hit. On a hit, with any object less than 5 lbs, you do twice your wisdom modifier in damage (minimum of 2 hp) damage. Any hit with an object heavier than that does 1d6 plus your wisdom modifier. The Dungeon Master determines the damage type based on the shape/nature of the object.

Playing Possum

Sometimes its best to just lay low. At 10th level, you gain the ability to make your opponents think that you died, but are instead placed under effects similar to those of feign death. If you use this feature on yourself, you can end it prematurely. You can also signal your teammates within 30 ft of you and use this feature on a number of allies equal to your wisdom modifier.

You regain all the expended uses of this feature after a long rest.

Trap Disabler

No trap is capable of fooling you. Starting at 15th level, you gain proficiency with Thieves tools. Additionally, when you encounter a trap or face an area effect that requires you to make a dexterity saving throw, you take no damage on a success, and only half damage on a failure.

Superior Planning

Superior Strategy

You and your team have learned flawless teamwork and perfected the skills in multitasking. At 18th level, you can use 2 strategies at once without consuming an extra use.

Thinking Ahead

You have become so in tune with the enemy's every move that rarely anything is outside your expectations. At 18th level, you can no longer be surprised. Additionally, once per long rest, as an action, you can enhance your focus so that you gain the benefits of equal to those of foresight.