If you are talking about AAA themeparks, I would have to throw SWTOR into that category. I think playing dark side on the empire lets you do some pretty evil things. I don't think it gets much more evil than lying, torturing and wantonly murdering people. But that is scripted and you are forced down a predetermined path of evil. It's not very meaningful, unless you like to be scripted into the role of being a villain. 

I think SWTOR would give you what you're looking for, though.

If you want to be evil (or good) in a more free form environment, you could play a game like Mortal Online or Darkfall: UW and go around camping noobs and taking all their stuff. But it wouldn't be very meaningful, I think, because there are a lot of evil players by that definition, so you wouldn't stand out much unless you were really focused on it. The better players would just find it pathetic. 

Star Wars the Old Republic

Lineage 2

EVE Online

All 3 of these games will allow you to be truly evil.

SWTOR doesn't allow you to be evil. It allows you a semblence of evil. It's produced evil. Very much evil-lite. May as well be called "I Can't Believe It's Not Evil."

You can choose path to the dark side for every class in SWTOR...

Here is my favorite compliation of evilness in SWTOR on video:).. though it's not the most extreme...

http://www.youtube.com/watch?feature=iv&annotation_id=annotation_115040&v=dUydrvpExHI&hd=1&src_vid=DWkmXrYW1Xw

Originally posted by DSWBeef
Seriously whens the last time a AAA game let you be truly evil? Im not talking about being renegade in ME im talking about what if you could have joined the reapers? The last thing I can remember is Warhammer online and Fable 3. Games now these days are all about being the hero. I wanna be the villian. What about you? 

Fable 3? NOT AN MMO.

Anyways, EQ1.

Only game that was "themeparky" that had true honest to god factions.  You could kill any NPC anywhere, anytime.  Well, you could try.  Obviously some NPCs were gonna kick the bloody shite out of you.  But, if you wanted to tank your High Elf faction by running around the newbie zone hosing the newbie guards, you could.

Originally posted by DSWBeef
I posted this in the GENERAL GAMING sections. So im not just talking about mmos here.....

FO3

FONV

Skyrim

Dayz

X-series

In recent memory that's all I've got on the non-mmo front.

Skyrim 

Red Dead Redemption

Originally posted by dotdotdash

SWTOR doesn't allow you to be evil. It allows you a semblence of evil. It's produced evil. Very much evil-lite. May as well be called "I Can't Believe It's Not Evil."

 I think you've confused "chaos" with "evil"

Evil is the intent, as in where you have decided to do harm to others to further your own goals (regardless of what your goals might be).

Chaos is the act of acting without regard for others or rules itself.

That's why in D&D there is the bi-direction scale of Lawful Neutral Chaotic and Good Neutral Evil for Alignment, so you can distinguish what type of personality you are (rational, irrational, unpredictable, etc) instead of just what kind of person you are (good ort evil).

I think it is fairer to say that in swtor you are allowed to be evil, but there are more constraints to it (ie. lawful mostly, you can't really go out and kill random vendors like a maniac).

As we speak. Age of Wushu. Not only pure evil, but varing degrees of evil, neutral and good.

I'm playing a pure evil character. I've done almost no good. There are some people that are not as clean cut. For example lets say you've done 100 evil deeds and 51 good deeds. That person would be classified as a lunitic. The system allows you to be you. It ill classify you accordingly without you having to chase it. 

Not only are there ranges, but there are rankings and titles and punisment. Punishment given if you school is not evil, but you are constantly doing evil deads. 

Evil deeds don't just come from killing either. It's the most in depth alignment system I've played. All the way down to NPCs treating you differently depending on alignment. 

Depends on what you mean by truly evil, OP.

In Mortal Kombat 9, you kill people as brutally as possible because some guy says so.  In SWTOR, you are evil, but you do have a code, so it's Lawful Evil if we're going by D&D terms.   In Dungeonland, you throw around a bunch of cute looking monsters that kill your friends brutally.  Is that evil?

In the AVP games, you can play Aliens and Predators, and some would call those evil.  In Man Hunt, you make snuff films.  In a lot of open world games, like GTA and Skyrim, you can do some really evil things.

At the end of the day, the game where I felt that I was a truly dark-hearted true master of evil though, was Legacy of Kain, the 1996 original (less so in the sequels).  You walk by and people are pleading for you to help them, and you hit them will a ball of vampire magic that rips off their flesh, lol.  Or, you drain their blood, or transform them into a pile of maggots, or whatever.  What made the game really stand out though, was the amazing voice descriptions of each power, detailing how much Kain delighted in the agony he was causing.  Good times.

Originally posted by DSWBeef
Seriously whens the last time a AAA game let you be truly evil? 

Like poisoning the neighbor's dog to punish the neighbor?

Or doing mutation experiments on a captured enemy?

You can do that in World of Warcraft.

Do you mean joining a guild, working your way to their elite guard and then, in the middle of a fighting tournament being watched by tens of thousands, turn on your own team and slaughter them - all part of an elaborate act of vengeance against one of the guild leaders that slighted you years before?

You can do that in EVE Online.

Do you mean forcing another player's character into the slave trade or, for a quicker but probably less profitable fix of evil, just rape and torture them for a while?

You can do that in Sociolotron.

In single player games, you've got GTA, Skyrim, and Saint's Row as three high profile examples.

There are different ways to be evil or play an evil character (two completely different things) and several MMOs support one or both to varying degrees.

Originally posted by DSWBeef
Seriously whens the last time a AAA game let you be truly evil?

Never. Milqtoast evil is the best you can manage, while still maintaining your account.

"True" evil requires you to violate other player's rights,