Hello there!

I've been planning to roll up a Master Manipulator kind of character - Think Palpatine from Star Wars or Littlefinger from Game of Thrones - and right now I'm just doing my homework on how to roleplay such a character as I've never done it before and I want to make sure that I put up as good a performance as I can, especially because I know that this might clash with the party a bit and I wanted to keep full-blown confrontations between PCs to a minimum.

So, to those that have already played such a character, do you have any tips for me? Any beginner mistakes I should be aware of and try not to make? Somethings that I should avoid under any circumstance or maybe things I should try to do as often as possible? What are some of your experiences playing characters like that?

It is a bit of a broad question, but any and all help is welcome and I thank you in advance for answering, or even just considering to do so.

I would say play a rogue mastermind, with high charisma and intelligence (if you want to be smart) or wisdom (if you want to be streetwise). I would say that you should not RP yourself as super AMAZING, maybe just when the time is right. Make sure that you don't use cheesy catchphrases, make something original. Skills: insight, perception, deception etc. Hope the character goes well. 

For the character stats, high Charisma, high insight (to tell what others want) and high Stealth (to eavesdrop). Deception (to trick people into believing you) and Persuasion (to persuade people into dong what you want) should be your highest skills.

For how you manipulate, make sure to make someone or something out as the 'enemy', whether they actually are or not. You can put yourself in a position of power by making others believe only you can protect against this 'threat'. 

As for roleplaying, look up Wormtongue for LOTR, he's a very good example of this kind of character.

Lastly, your alignment should be lawful or neutral evil.

I think a College of Whispers Bard is a perfect subclass for a Wormtongue type manipulator.

There's a few different class abilities that could be thematically appropriate for your concept, depending how far you want to cross over the line from "manipulating" to "commanding."

• Order Cleric is one of my favorite subclasses, taking the thing that Clerics are good at but which is often boring (casting heals and Bless every combat), and turning that into generating an attack by your ally. Beyond their 1st level ability, the level 2 and 6 abilities also help you exert your will over the battlefield in new ways or more easily, but past that the features kind of dip back into "regular cleric" stuff.
• Mastermind Rogue is kind of forgettable, but the level 3 feature that allows you to Help as a Bonus Action from 30 feet away is fairly unique. A lot of other classes, specifically casters, often don't have much to do with their Bonus every round, so being able to hand out advantage for free every round with your Bonus is some nice action economy.... and gives you a lot more opportunities to fill the airwaves with your insidious urgings.
• Bard, obviously, involves a lot of handing out inspiration dice. But the College of Glamour in particular gives you some very manipulative abilities at 3, 6, and 14. Charm an entire room full of people after a performance(/speech) at 3? At will casts of Command which can't fail, for 10 rounds at 6? 14 is essentially just a better Sanctuary, but still, manipulating enemies into not attacking you for 10 rounds? All good stuff.
• Great Old One Warlock lets you whisper insidiously directly into others' minds with telepathy. At 14, you can create perma-charmed Thralls against incapacitated targets... but all the Charmed condition really does is prevent them from taking hostile actions against you (+ whatever loyalty/friendliness that your DM decides is appropriate, but which isn't necessarily required by the base condition itself). Incapacitated happens more often than you might think, since sleeping=unconscious=incapacitated!
• School of Enchantment Wizard has some very manipulative features at 2 and 14. At 2, you get those eyes that the snake had in Jungle Book, able to hypnotize (Charm and Incapacitate!) others for as long as you stare into their eyes. And at 14, you can start actually manipulating memories, tricking enemies into thinking there's cause to be friends, that sort of thing.

Oh also, take Inspiring Leader, no question about it. Nothing will make people listen to your propaganda and nonsense more than getting a huge THP boost from it every short rest :)

One or a mix of multiple of these classes would make a mighty fine manipulator.  In my book, a Cleric 2/Rogue 3/Bard 6 would be the skeleton of a really savvy manipulator, able to hand out free attacks, hand out free advantage, and directly hijack enemies for entire combats or scenes if necessary. You don't need more than 13 or 14 Wisdom, because all you'll be using Cleric spells for is buffs, or much more than 13 or 14 Dexterity because you'll be wearing heavy armor and attacking with Charisma cantrips (or not attacking at all), instead of fishing for SA. How you want to flesh it out past that is up to personal taste.

You should have an out of character talk with your group about it, explaining what you plan to do. Not so much to ask permission from them as warning them of what your character will do. Check and see if there are any lines you should be sure not to cross. As you say, there could be some  intra-party conflict this generates, make sure it stay in game and not real life. 

Along what Xalthu said... I think what helps a high-charisma manipulator like this have fun at the table (and be fun for the other players), is to decide from the outset not to be the leader yourself, but to instead to pick another player in the group that you're going to be assisting and throwing your weight behind. Bonus points if they're a dumb mook (Paladin or noble Fighter type) who isn't really intellectually or emotionally qualified to be more than a figurehead. The tension that's created by you setting up plots and opportunities, and then your leader either bungling them or going a different way with it... it really creates some more interesting drama than you just facerolling through Persuasion checks on behalf of the party, and involves more of the party in social encounters than is normally the case. 

I am of the opinion that a character like that either has to be running their own campaign or has to have some ability to see more of the chessboard than their colleagues.  I think I’d talk to the DM about using the kind of divination spells that DMs usually hate.  Augury, commune, contact other plane, etc.. Your guy has to know towards what end they’re manipulating things, or else they’re just a con artist.  A con artist can also be a fun character, but you seem like you’re aiming higher.

As far as roleplay goes, my favorite example of an evil manipulator is T.A.O. from Alan Moore’s mid-90’s run on WildC.A.T.S..  My favorite example of a good manipulator is the seventh Doctor Who, Sylvester McCoy.

I think at level 1, your a regular ol Druid or ranger or whatever-you don’t ‘roll up’ a master manipulator.  You become one....

but start with persuasion and go from there.

Start as a bard, rogue, sorcerer, or warlock. Anything else and you are doomed. If rogue, get expertise in Deception and Persuasion.

Quote from Xalthu >>

You should have an out of character talk with your group about it, explaining what you plan to do. Not so much to ask permission from them as warning them of what your character will do. Check and see if there are any lines you should be sure not to cross. As you say, there could be some  intra-party conflict this generates, make sure it stay in game and not real life. 

 This x 100. If you ever think your character might cause intra-party conflict, get buy-in from the other players. Discord within the party is a total deal-breaker for some players, and others may really be into it and build their characters specifically to be your foil or accomplice. Either way, they should know up-front.

Mechanical/Gameplay Tips:

1. What Xalthu said, but to add to that, don't act against your party members' interests. As a DM, nothing makes me roll my eyes harder than two players rolling skill checks against each other. It's dumb, it breaks up the flow of the game, and it threatens party unity. If you want to play a manipulator, make sure your character has a hard line they will not cross: My party is off limits.
2. Also talk to your DM. Frankly, most DnD campaigns aren't built for high intrigue. A "master manipulator" is working a long game - something that might take months or years to fully realize. Not only does a DM have to be willing to put in the work, but they also have to adjudicate your decisions fairly, and find a way to fit your character's schemes into a game with three to four other players. I've been running games for twenty years, and I'd be more inclined than not to flat-out veto this character concept unless you made a really compelling argument to keep it.
3. Rogue and Bard are obviously ideal for this. Bard more-so, because they get access to enchantment and illusion spells. Arcane Trickster can also pick this up, but is less effective in general.
4. Don't underestimate the value of the History skill in this capacity. Understanding the history of a kingdom and its royal lines will do more to drive your understanding of their deep-seated desires than any Insight check you'll ever make.
5. Deception is for suckers. See below.

Suggestions for play:

1. Know your goal. Your goal will inform the kind of manipulator you're playing. Emperor Palpatine wants to rule all the galaxy, Littlefinger wants to rule all of Westeros. PT Barnum wanted to separate suckers from their coin and skip town. A long game calls for different strategies than a short con. Loftier goals require a longer game, require more complex strategies. If you're new to the concept of intrigue, keep your goal fairly manageable. "Become the god-king of all the planes" is harder to keep track of than you'd think.
2. Deception is for suckers. If you're playing a long game, all a lie is going to do is present you with a loose string you can trip over later. Instead of lying to someone, tell them the truth they want to hear. Instead of stealing something, learn their heart's desire, then offer it to them. They will beg you to take the thing you want from them, and you'll look like a hero when you accept. "What's that Lord Pinchpenny von Pious? No, I couldn't possibly accept a reward, I was simply bringing Pelor's light to the dark recesses of the Oerth. What's that? A royal ball, you say? Tonight, you say? Well, I'm sorry, but my companions and I have been riding hard, and haven't anything to wear. I don't see how we could secure access to a bath and a tailor on such short - oh, my lord, you are TOO generous!"
3. Palpatine and Littelfinger are weak sauce. You're discussing contemporary reimaginings of age-old characters. Look to the source: Iago from Othello, Richard from Richard III, The Count of Monte Cristo. All are deeply brilliant schemers, each playing successively longer games with successively more intricate goals. All three are tremendously well-written, because they make you love them, even as they make your blood run cold.

@DesRploid: You've gotten some very good advice in this thread. I just wanted to add one small but important thought. No matter which class or skills you choose, remember that (unless you start at fairly high levels) you're not going to be a "master" manipulator right away, even if you do have expertise in certain skills. Some character ideas don't fall into place until they have gained a few levels and that's OK. Everyone has to start somewhere. 

You might not also be a master even if you do start at higher levels, just because you as a player need to get a feel for the character (this is where all the good advice comes in) and that is also OK. However, if you think that you're not going to have fun playing a character that need a few levels of practice to really shine, it's also OK to play a different character.

Good luck, have fun!

If you want help on building one you’ve gotten lots of advice here already. If you want help roleplaying one, you should watch a show called Leverage.

I would 100% go with shadow bard since Char is your dump stat and the subclass benefits are perfect for impersonating people and sewing fear. This also opens you up to lots of great spell possibilities. I would lean towards spells that are good for deception or getting secrets out of people because secrets = blackmail. So things like detect thoughts, various illusion spells, zone of truth, charm person, friends, ect. I would also consider some spells like vicious mockery, comprehend language and message- basically make communication your strong point.

as for feats, if you are not multi-classing into rouge i would take the Half-elf feat "everybody's friend." for the double proficiency in persuasion and deception checks.
other feats to consider would be linguist, inspiring leader, keen mind, or observant- all things centered around finding secrets and inspiring the crowd.

as far as play style goes, one thing i would keep in mind is that your manipulator will likely be aware that some of the most powerful people they will encounter are the ones in your party- anyone in their right mind would ensure that they are in their good graces of such a party. Treat them well and go out of your way to help them so they will be more likely to take your side in things.  preferably dont focus so much on manipulating them into doing what you want. Instead convince them that you can get them what they want- if they are willing to go along with your plan. (and who knows, maybe the plan is a little more extreme then anyone expected.) 

If you want to hide your true intentions, consider downplaying your intelligence and either being the party goof or comedy relief. If people are always used to you joking around, true cunning will often be taken for a gag or a crazy accident and it will take longer for people to realize that you are 1) dangerous and 2) serious.

consider framing your reasoning as being for the greater good (the council is corrupt and im encouraging the people to overthrow them!) and then using a disguise/alter ego for your more devious schemes so they dont get traced back to you.

when it comes to the common rabble, you could always use your crazy high charisma and persuasion bonuses to sway them to whatever cause you desire. you want to start a cult or a revolution? Easy. You want to start a mass panic to distract from your real plan? the commoners are your canvas.  

as for the higher ranking individuals, your ability to disguise yourself and read lips/minds/cast friends ect would be of perfect use here. use it to gather information and then pose as people of importance and say just the right or wrong things to ruin a reputation or get what you want.

Try to avoid directly manipulating the party. if you dont plan on keeping your deeds a secret from them, maybe convince them that your talents are at their disposal.

It is not clear to me who you intend to manipulate?  Do you plan to manipulate party members?  I'm not a big fan of that since it takes away from their agency and sows discord.  Are you planning on manipulating the local government officials or guards?  This might be fun for the party but sounds like you're headed down an evil party path of adventure.  Is your party on board with making enemies from the bystanders that figure out what you're doing?  For example, if you Charm someone, they know it, whether you were successful or not, and they should react accordingly.  Or are you trying to manipulate things on a grand scale?  This can be by evil or good intent.  St. Barnabas was called the Spirit of Reconciliation.  He was known for diffusing strong emotions and getting people to work together.  That is manipulation, but for good intent.  Or you can be a Godfather and manipulate things on a wide scale for evil intent.  But now your party is your inner circle so you should be pretty straight up with them, provided they are OK with playing second fiddle.

I am playing just such a character, the good kind, that seeks to do a lot of good for folks so he might call in a favor later when he needs to diffuse a volatile situation.  He does this by buying goods and selling goods.  Along the way he gives some of these goods away or sells them for well below market value to earn goodwill.  Later in the game he hopes to obtain information and persuade folks to set aside their differences for the greater good.

But there are many ways to play a manipulator.

High Charisma, Persuasion, Intimidation, Deception, Perception, Insight, and possibly stealth, although that can be done by others in your party if you are able to accept and expect their help.  High Wisdom and Intelligence will be needed so you'll have low Strength and Constitution.  This sounds more like a Bard than any other class to me.