(Homebrew by Benjamin Huffman on DMsGuild. Due to the commercial nature of this homebrew, it will be provided to players if they want to play this Class)
Arrows rain down around her as she runs towards the hobgoblins. Desperate to close the distance, the half-orc fights through the sting of a dozen cuts to reach her foes. The pain only makes her stronger. As she descends on the snarling pack she swings wildly, knocking several hobgoblins off their feet and sending the rest scattering before her.
The human braces himself for the impact as the orc rushes him. Then the monster makes a mistake, telegraphing its next move, and that's all the opening the human needs. He ducks beneath the orc's wide swing then raises both hands high above his head and brings them down on the orc's back, forcing the brute to the ground.
The dwarf smiles broadly and chuckles as the petty noble raises his hand to strike him for the impudent remark. Quick as a flash, the dwarf shatters the bottle in his hand against the bar and brandishes it before the noble. The young dandy flinches, stumbles backward, and runs away as the dwarf turns back to the bar to order another round.
Wherever they come from, pugilists live a rough and tumble life that leaves them full of determination and reckless, either from overconfidence or desperation. In a fight they can channel this strength of character to dig deep and fight off foes with greater strength of numbers, arms, or armor than anyone else would think possible.
Swagger for Days
Pugilists unconsciously tap into their own inner strength in the form of moxie. This is not an esoteric or mystical energy that flows through the multiverse, but the result of determination forged over a lifetime of hardship with a never-say-die attitude. You can teach someone how to fight but you could never teach someone how to be a pugilist. The secret of mastering moxie doesn't come from disciplined study or rigorous training, it comes from years of wanting and needing
Life on the Street
Every city in the worlds of D&D has its back alleys, its underground fighting rackets, its ghettos. The pugilists who live in these places don't have time to consider the lofty ideals of philosophy or ponder the mysteries of the universe. The pugilists, growing up on the wrong side of the tracks, spend all their time chasing down their next meal or, if they're fortunate enough to have that, their next drink, bedfellow, or flophouse.
For pugilists, becoming an adventurer might be the only way out of whatever miserable situation they've been stuck in since infancy. For others, getting lost out in the world is an escape from the tangled web of debt or enemies they've piled up. Other pugilists fight because it's the only thing they know how to do. Whatever the reason for their adventuring, pugilists are as excited by the prospect of throwing punches as they are spending every last gold coin they earn.