The bar fight (aka pub brawl, aka tavern melee) is a classical trope of all fantasy role-playing games. Back in the old days of 1st and 2nd Edition Advanced Dungeons & Dragons, the wizard was the least likely to partake of the bar brawl. It's a simple matter of cause and effect (or possibly supply and demand). Wizards require high Intelligence scores, tavern smashing requires a certain level of inebriation, and beer destroys brain cells. So the stoic and sober wizards would nurse their milk in the corner and try not to get hit in the face...
Enter 3rd edition Dungeons & Dragons! And the introduction of the SORCERER class. An arcane spell caster whose magic is based on Charisma rather than Intelligence. Now we have available a person of mass destruction (at 5th level anyway) that can partake of drinking, fighting and purging in the adventuring party.
Drawn using Clip Studio Paint Pro on a Surface Pro 4. Here is the time lapse video showing my (patent pending) QuickPaint process:
And here is the B&W line art version (to make it look more like 1st edition):
