Street Brawler
This subclass of Fighter is adept with being outnumbered and letting enemies be each other’s weaknesses. This fighter also specializes in maintaining their surrounded state and does not let people escape.
Come Get Me, You Fools!
Beginning when you choose this archetype at 3rd level, you have a knack for being flanked.
You are immune to the flanked condition. Additionally, while you are being flanked and not wearing heavy armor, you gain a +2 to your armor class.
Nice Meeting You, Goodbye!
Also starting at 3rd level, you may use your bonus action to take the disengage action.
Hit Him, Not Me!
Starting at 7th level, you gain the ability to redirect attacks while flanked. When a creature within your melee range misses you with an attack, you may use your reaction to have them roll the attack against another creature within your melee range at disadvantage.
I Didn't Say I Was Finished!
Starting at 10th level, making an attack of opportunity against a target leaving your melee range no longer requires the use of a reaction.
Me First!
Starting at 15th level, as a reaction to a creature within your melee range taking their action, you may burn an action surge to take an action on their turn.
If they were attempting to cast a spell or another ability which would require concentration, they must succeed on concentration Saving Throws to maintain their casting, or else their action is wasted.
Worry Not, I Saved Some For You, Too!
Starting at 18th level, you are the master of outnumbered combat and thus can use your sudden bursts of focus to put the pain on all those foolish enough to face you.
On your turn, you may use an action and a use of your action surge ability to make a montage worthy attack on all your foes, using them to hurt themselves and swift motions to hurt everyone.
When this is used, you may take a full attack action on each creature within your melee range.