Really, there are two separate issues being discussed here. Roleplaying as an antagonist is quite a different subject from roleplaying as a villain, and the frequent mistake I see being made is in believing that "antagonist" and "villain" are interchangeable terms. They're not.Â
With that in mind, I will move forward in my assumption that Emberhair is specifically referring to roleplaying as a villain, not necessarily as an antagonist.Â
You're on the right page as far as communicating OOCly and making sure heated interactions never become personal between two players. That said, it's usually never fun to roleplay with someone who is a dick just for the sake of being a dick, not because that character is unlikeable in a moral sense, but because most characters who are roleplayed as jerkwads are flat, one-dimensional, and boring, with completely arbitrary behaviour and habits that fail to establish any significant consistency. Such characters come across as idols of self-indulgent wish fulfillment, and subsequently fail to be believable as people.
This subject would be very easy were we simply talking about a story, but roleplaying is something different. In roleplay, a villainous character is 99% of the time someone you can't get rid of, an obstacle that can never be fully overcome. Thus, in order for interactions with characters who are "bad" in the moral sense to be meaningful and reasonably frequent, there is one absolutely critical thing you must establish, and that's depth.
It's the most difficult and most important aspect. Like I said, a character who is a dick just for the sake of being a dick is boring for the same reason that a goody two-shoes Lawful Good hero guy is boring. There needs to be reasoning, motive, and impulse behind their dickish actions. Said reasoning and motive doesn't need to be significant (although that can certainly help), but it does need to be present, even if it's something random, unexplainable, and petty, like "Miqo'te ears really piss him off" or something similar. Why does your character snap? Why does your character constantly mock others? Why does he get sent into fits of rage? Why is he racist? Why is he arrogant? Why is he lazy or flaky?
In addition to the above, it's important that your character isn't a dick all the time, unless you fully intend on killing said character off somewhere down the line. It's not as if he needs to spend half the year being Mother Theresa and the other half of the year being Heinrich Himmler, but there need to be certain occasions--even if they're specific or rare occasions--where he can be seen as something other than a complete prat. That's the entire purpose of depth: to demonstrate that a character isn't just an archetype with stock traits (i.e. one-dimensional), but a person, with moods and attitudes and perspectives and opinions that come together to define someone we're supposed to care about.Â
You need to somehow convince your readers that something within this character can be counted as a redeemable quality, even if that single redeemable quality is completely outweighed by the irredeemable ones. Even if you want to keep your villainous character as a complete asshole who will never, ever change his fundamental behaviour, your readers still need a reason to care about what happens to this character and a reason as to why their own characters should interact with your villainous one. If your character is a sociopathic narcissist who frequently robs, steals, and insults others, other characters will have absolutely no reason to interact, and the RP is dead in the water.
Depth is absolutely critical if you plan on roleplaying any kind of morally depraved character outside of a Disney villain or the Big Bad Evil Guy of a D&D campaign. In the latter settings, it's perfectly fine to be flat in their evilness because in those cases the villains aren't characters, they're simply plot devices disguised as characters used solely to encourage the growth of the hero and thus their depth is unessential.
In RP, however, you want your villainous character to be seen as a person. You want them to be as interesting as they are unlikeable, you want other players to be fascinated by this huge douchebag, you want to give them reasons to continually involve their characters with yours.
And to do that, your character needs to have depth.
With that in mind, I will move forward in my assumption that Emberhair is specifically referring to roleplaying as a villain, not necessarily as an antagonist.Â
You're on the right page as far as communicating OOCly and making sure heated interactions never become personal between two players. That said, it's usually never fun to roleplay with someone who is a dick just for the sake of being a dick, not because that character is unlikeable in a moral sense, but because most characters who are roleplayed as jerkwads are flat, one-dimensional, and boring, with completely arbitrary behaviour and habits that fail to establish any significant consistency. Such characters come across as idols of self-indulgent wish fulfillment, and subsequently fail to be believable as people.
This subject would be very easy were we simply talking about a story, but roleplaying is something different. In roleplay, a villainous character is 99% of the time someone you can't get rid of, an obstacle that can never be fully overcome. Thus, in order for interactions with characters who are "bad" in the moral sense to be meaningful and reasonably frequent, there is one absolutely critical thing you must establish, and that's depth.
It's the most difficult and most important aspect. Like I said, a character who is a dick just for the sake of being a dick is boring for the same reason that a goody two-shoes Lawful Good hero guy is boring. There needs to be reasoning, motive, and impulse behind their dickish actions. Said reasoning and motive doesn't need to be significant (although that can certainly help), but it does need to be present, even if it's something random, unexplainable, and petty, like "Miqo'te ears really piss him off" or something similar. Why does your character snap? Why does your character constantly mock others? Why does he get sent into fits of rage? Why is he racist? Why is he arrogant? Why is he lazy or flaky?
In addition to the above, it's important that your character isn't a dick all the time, unless you fully intend on killing said character off somewhere down the line. It's not as if he needs to spend half the year being Mother Theresa and the other half of the year being Heinrich Himmler, but there need to be certain occasions--even if they're specific or rare occasions--where he can be seen as something other than a complete prat. That's the entire purpose of depth: to demonstrate that a character isn't just an archetype with stock traits (i.e. one-dimensional), but a person, with moods and attitudes and perspectives and opinions that come together to define someone we're supposed to care about.Â
You need to somehow convince your readers that something within this character can be counted as a redeemable quality, even if that single redeemable quality is completely outweighed by the irredeemable ones. Even if you want to keep your villainous character as a complete asshole who will never, ever change his fundamental behaviour, your readers still need a reason to care about what happens to this character and a reason as to why their own characters should interact with your villainous one. If your character is a sociopathic narcissist who frequently robs, steals, and insults others, other characters will have absolutely no reason to interact, and the RP is dead in the water.
Depth is absolutely critical if you plan on roleplaying any kind of morally depraved character outside of a Disney villain or the Big Bad Evil Guy of a D&D campaign. In the latter settings, it's perfectly fine to be flat in their evilness because in those cases the villains aren't characters, they're simply plot devices disguised as characters used solely to encourage the growth of the hero and thus their depth is unessential.
In RP, however, you want your villainous character to be seen as a person. You want them to be as interesting as they are unlikeable, you want other players to be fascinated by this huge douchebag, you want to give them reasons to continually involve their characters with yours.
And to do that, your character needs to have depth.
