So I'm mingling on how to maximize a variant human with a Charger and Great Weapon Master feats (Glaive user). For a sacrifice of -5 to attack rolls it can get a +15 damage (+5 for charger and +10 for GWM), but that can only be done during that one time Bonus Action. (so now extra attack here guys). Do you have any tips on maxing out damage output on that feat combo from level 1 to 20? This is without the buffs from other characters and without any magic items. As far as my research has gone, this is what I've got:

- Basic Poison applies poison damage if applied to piercing or slashing weapon

- LVL 4 RANGER: Ranger Archetype: Hunter with Colossus Slayer (adds a 1d8 damage to a creature whose hp is below its max hp), Hunter's Mark spell

- LVL 3 FIGHTER: Fighter Archetype: Battlemaster's maneuvers that adds a superiority dice to damage, and the precision attack to compensate the -5 attack roll

- LVL 2 WARLOCK: Pact of the Blade (summon glaive), Warlock Archetype: Hexblade using the Hexblade Curse (use proficiency bonus as additional damage), Eldritch Invocations: Devil's Sight (to counter dark places), and Improved Pack Weapon (+1 to attack and damage rolls)

So from the covered buid I can get:

FOR ATTACK ROLLS: (1d6 superiority dice) + (1 from Improved Pack Weapon) (MIN: +2 / MAX: +7)

FOR DAMAGE ROLLS: (1d8 Colossus Slayer) + (1d6 Hunter's Mark) + (1d6 superiority Die) + (+4 proficiency from a level 9 character using the Hexblade Curse) + (1 from Improved Pack Weapon) + (1d4 (DC Save of 10 Con) from the Poison, Basic) (MIN: +9 / MAX: +29)

From there I still have 11 more levels to go. Care to share your thoughts?

I think Charger is a weird fest.  It can only be used to give a single bonus attack if you Dash as an Action.

Any class with Extra Attack will either never use it, because it sacrifices a full attack, or it's only used as an Edge Case scenario.

The only Class I think could benefit from it on a consistent basis is a Swahbuckling Rogue.  They can move away from a target if they attack without an AoO.

Since Rogues only attack once a turn a Swashbuckler could Dash every turn for Movement x2, and attack as a Bonus Action with Sneak Attack and +5 damage from Charger.

Well a rogue would be appropriate for the Charger feat, but it already has the "Move in, Hit, and Bonus to run away" thing which makes the Charger useless. A common calculation for my taste. I was aiming for an unorthodox build for a one hit melee burster who can go in, force all damage in one hit, and get out. Like how medieval lance wielding knights do it. So Charger / Great Weapon Master has to stay. 

The problem is the only simgls hit damaging attacks that scale after Extra Attack or lvl 11 are damaging cantrips.  You can't use those with Charger.

A mounted fighter with a Lance is better off making use of Extra Attack.

The Rogue already can effectively use Charger with a Bonus Action Disengage, or Dash in the case of a Swashbuckler, it does consistently add another +5 damage every turn.

Charger is meant to give you an option in situations where you can't reach your enemy without dashing. It's not meant to be your main form of attack.

There's much better ways to build a hit-and-run character, like the Mobile feat, mounted combat, the Zephyr Strike, or subclasses like Swashbuckler (Rogue), a Way of the Drunken Master (Monk), or Gloom Stalker (Ranger).

Quote from InquisitiveCoder >>

Charger is meant to give you an option in situations where you can't reach your enemy without dashing. It's not meant to be your main form of attack.

There's much better ways to build a hit-and-run character, like the Mobile feat, mounted combat, the Zephyr Strike, or subclasses like Swashbuckler (Rogue), a Way of the Drunken Master (Monk), or Gloom Stalker (Ranger).

 That is exactly why us dnd players use it.

To break the game

Nothing about the quote breaks the game.

Im talking about using things that your not supposed to

What do you mean? Game features tell you things you can do. The fact that individual features can add together or be used in complementary ways is not an unintended consequence of game design. Game features that have interactions that aren’t widely known, talked about often, or whose uses aren’t immediately to people the first time they’re read doesn’t mean there’s some arbitrary limitations hidden within the game that the designers were hiding.

Frankly if a feature does almost anything other  than direct damage then there seems to be a a large percentage of the base who don’t bother trying to work out if a feature is useful in other ways. Then there seems to be a sort of biased rejection of the usefulness or the legitimacy of features by those same people when others spend a bit of time parsing out what a feature might do that they chose to blatantly ignore in the first place.

there is also the phenomenon that seems to take place that, when a feature or rule is first interpreted, that interpretation seems to stick very firmly, regardless of how accurately it was understood. Perhaps this has a deeper relationship with how we learn rather than the game mechanics themselves.

If you really want to be a charger, take 2 levels in Rogue. Dashing as a bonus is just way better than being able to attack as a bonus when you Dash as your Action.

I get what Bruenor is saying - it can be fun to find loopholes and synergies that allow you to use something in a way that it was not intended. Unfortunately, the memories of 4e charge optimization were fresh in the devs' minds when designing 5e, and they shut that down hard this time around.