What does that mean?
What does "genuinely evil" mean to you? And "in a realistic and serious manner"? What would be an example from say a movie or book that fits your definition?

Early in the Sims series I used to do everything possible to break my characters will by starving them, making them collapse from exhaustion and then just when it could get any worse for them;

- Pause the game
- Build a wall blocking any exit
- Light some fireworks

It ends up looking pretty messy.

In the real world people who commit random murders (and make no effort to hide it), threat everyone like shit, and let everyone know exactly how "evil" they are won't last very long. They'd get arrested before they managed to accomplish anything of note.

The problem is, the really evil characters often act like the good guys. They say the nice things. They donate money to charities. They help the poor and the sick. Meanwhile, they're arranging the genocide of their enemies. They're manipulative.

Worse than them is the people who genuinely believe they're doing the right thing: Again, the problem is that in game these people will often do the "good" stuff according to the game's rules. They don't care why you do something just care if you pick the "good guy" option or the "bad guy" option.

The flip side to this though is that genuinely good characters can be assholes who treat everyone like shit. Good is not nice.

Best movie examples I can think of: Henry, Natural Born Killers and Romper Stomper.
I generally don't watch these kind of movies so I simply don't know of any others.
Anyway, these are the kind of lead characters I would describe as 'genuinely evil'.
I have not played a game where the protagonist has been like this.

By 'realistic and serious' I refer to cases where the evil protagonist is not depicted in a humorous or cartoonish manner (either visually and behaviorally), or where the medium (film, game etc) does not aim to make you sympathetic towards them, turning them into anti-heroes.
In video games it tends to be one or the other.

I recognize that this can be highly subjective though, as 'sympathy' can be experienced differently.
In the above movies I never felt sympathetic towards the lead characters, very much the opposite.
However with the Sopranos, Breaking Bad and Dexter tv-shows I did feel sympathetic towards the lead characters.

Maybe I simply see video games as "just "games. They don't translate into realism for me.
So to me the very idea of 'evil' in a video game is almost absurd, at best its only a caricature of evil in real life.
To answer the OP's question I took the liberty to interpret 'evil' in my own way.

I rarely enjoy playing evil, because in gaming it mostly boils down to doing the most destructive things possible and lacks any logic. Playing evil by deceiving and taking advantage of everything without others knowing that you are doing that would be more realistic but I don't know a game where this is possible besides some passages of Fallout and Gothic.

Well, I enjoyed playing an imperial pilot in Tie Fighter though but only because of the ship and mission designs
and playing as NOD in Command & Conquer always was a lot of fun due to their tesla towers.

I'd like to play a rebel against a police state some time but not sci-fi but more settled in our time, I wouldn't call that evil though.

it's also the second stupidiest choice in this game (first is sidding with Ming) :)


I enjoyed being evil in Black and White. puny peasants. I need more energy!

But rarely games give you an option of being evil. Petty yeah. but not trully evil. and rewards suck most of the time. Except KOTOR. Where being evil was viable choice and gave you bonuses as good as being good. KOTOR2 did it much better of course (being obsidian game). The mission during civil war was absolutely brilliant. You were not an asshole, a jerk like in 'evil' sides in KOTOR1 and other bioware games. You were immoral, goal oriented who had a mission to accomplish. Your demands from the new ruler and how you treat him (and how he treats you with respect which also rarely happens in games) was written incredibly well. True evil. Not asshole thug who has issues.

When getting revenge on someone that has done something completely heinous against my own character, or some undeserving NPC in an RPG. That always gets some great satisfaction from me.

I don't typically play outright EVIL but....

At times when playing Postal 2 I've done some horrifying things to some innocent bystander NPCs that I don't think is even mentionable here

I don't really enjoy being evil in videogames. I'm talking about the titles that offer a choice, because it is true that for example Dungeon keeper and other games where you actually are the villain to begin with are fun.
Titles with choices, usually RPGs, often don't seem mature enough for evil choices so when you do choose evil, you're not actually choosing an evil option, it's more like choosing a crazy stupid bully option. It's pretty much just beating someone up or threatening them with death unless they give you their lunch money.
That's just not really enjoyable.

Poorly-written / dysfunctional NPCs / sidekicks really tick me off and I typically look for ways to dispose of them. Nothing makes me hate a character more than poorly-written dialogue choices.

I killed Virgil in Arcanum. Couldn't stand him. ;)