They are known for a variety of fun ruining characteristics, such as taking the game too seriously, over competitiveness, and insulting everyone on their and the opposing team.
While the Bro Gamer and most other gamers get along, his mortal enemies are the Hardcore Gamer and especially the PC Gamer who find utter offense in the bro's generally poor or limited taste in video games, and over fondness of his console of choice. When these two types of gamers meet they often bring out the worst in each other.
Bro Gamer: Naw man!
Gamer: Super Meat Boy?
Bro Gamer: HELL NAW.
Gamer: Then what do you play?
Bro Gamer: BLOPS ALL THE WAY.
Gamer: I find your choice in games to be disappointingly narrow, but as a gamer who simply plays for fun, I don't think I could care less.
Hardcore Gamer: I'm playing VVVVVV. It's hard as hell, but oh so satisfying.
Bro Gamer: Man, shit. Those graphics be the opposite of hella dank, playa.
Hardcore Gamer: Get out.
PC Gamer: I prefer PC gaming because of the keyboard and mouse, as the mouse itself is unarguably a superior aiming tool.
Bro Gamer: Hell naw, bro. Controllers all the way! Don't need auto-aim or nothin!
PC Gamer: My bro senses are tingling. Also, get out.