How do I deal with a powerplayer at my table as a DM? What's your way to deal with these kind of guys?

How do I deal with a powerplayer at my table as a DM? What's your way to deal with these kind of guys?

A firm no followed by a friendly chat. Explain you're looking for a more relaxed game environment and don't want to make everyone optimize everything to stay on an even footing.

That or spray with a squirt bottle every time they start thumbing through splatbooks

As long as they're not ruining the fun of others I'll let them do their thing. If they are interfering with the others' fun I'll talk to them. If that doesn't work I'll subtly change my encounters so that they counter the powerplayers but not the normal players or just straight up kick them if I deem that it's not worth trying to fit them into the group.

Making combat encounters counter them to give them a challenge will result in them whining about it being too hard.
Talking with them about it might lead to them laying off their habit, or at least working towards doing so, or them getting angry since they can't see what they're doing wrong and blame you for not catering to their needs.
Throwing them out will remove all your problems but may or may not lead to you finding a "That DM" thread later on an online anime imageboard with a story that you recognise elements of. No matter what you do, you may find such a thread later actually.

what's a splatbook?

Do your other players seem like the player is ruining their fun by powerplaying? Have they complained to you?

I wouldn't worry too much about that, Veeky Forums will say absolutely anything in order to make sure every single hypothetical situation involving a GM ends with the GM being in the right and the player being "that guy" no matter what. I suspect there's a lot of bitter forever GMs here that feel the need to leap to another GM's defense in any scenario because they see it as an insult to themselves.

A supplement, like Complete Arcane.

Extra books filled with additional classes, equipment, spells, etc. Rather notorious for broken and ridiculous 3rd party stuff in the days of 3rd edition DnD.

While they can add a lot to a game, munchkins tended to pull from every published book they could to further optimize their dudes.

Generally speaking, relax and take stock of the atmosphere of the game. Is everyone having fun? If so, Johnny Quickenspell isn't really a problem.

If the other players are shooting the powerplayer dirty looks or seem to be greeting combat (or whatever) scenarios with a feeling that what they do doesn't matter, then you might want to experiment with altering your scenarios. Do NOT follow the advice of the psycho DMs who have told you to counter the powerplayer. This is a mistake and will make for a toxic play environment. Instead, give them a "target-rich environment". The other players are unlikely to resent the powerplayer for doing more so long as they get to do anything, so change up your scenarios to let the powerplayer chalk up a high body count while his buddies do other stuff. You can also exploit the "strongest man in the party" situation. For example, if you create a scenario in which the powerplayer holds off a horde of enemies at a chokepoint while the rest of the party solves a puzzle, everyone gets to have fun.

Powerplayer of my group here. You can't stop guys like me, our goal is to win the game and make the most efficient characters possible.

There's only so many times you can have one guy holding off a horde while the rest of the group feels useful for a bit. In my experience things really work best when everybody is on the same page about what they're trying to achieve with the game.

Case in point, here sees the system as an opponent to break so they can feel like they beat the game itself. If the whole group feels that way then sure, have an epic campaign where shit gets retarded. OP made it sound like he has one player bent on exploiting the system, which just gets tiresome.

Play 5e, rules as written, track everything, DM keeps the character sheets for everyone (a solid idea anyway,) in between games study up on every trait, ability, spell, feat, or whatever else appears on the sheet. Learn what spells need a free hand or actually consume materials, look up con checks, understand how the Concentration mechanic works for spellcasters now, pay attention to which "awesome" looking weapons have huge drawbacks in the fine print (lance in particular) and study the hell out of the very few troll-ish builds. (Double-wielding lances is surprisingly balanced because in exchange for becoming a massive mounted warbeast when mounted the player becomes a sub-par ranger when dismounted. The thunderwave steed mount is just trolling and doesn't vaguely work.)

But I warn you: do not skimp. 5e is a giant wall against 3.PF fuckwittery. Each houserule or exception you get talked into is like pulling a brick out of the wall. It doesn't take too many times listening to "but these multiclassing restrictions don't make sense" or "who wants to spend time tracking little stuff" or "why bother keeping track of two different kinds of spell slot?" fudges before you get suckered into okaying some *real* shit builds.

Take stock of what kind of player you're dealing with. In my experience as a DM there are three kinds of players; artists, engineers, and competitors. Artists prioritize character over performance and prefer interesting combinations and races. Engineers treat their characters like a car, seeking to cut away all fat and fine-tune them for maximum performance because just the act of doing so makes them happy. They like the numbers. And then there are competitors, people like who view the game as a competition and are trying to "win" by outperforming everyone, including the DM. If it's the former two then it's not much of a problem and there's nothing you can really do about it. It's just how they think. As the DM you have the option of challenging these players. Engineers might be a bit minmaxed but they're not there to "win." If it's the latter then you need to talk to him and explain that it's not a competition and that he's not going to win a trophy for outperforming everybody. He's really not going to accomplish anything but annoy everyone else.

>There's only so many times you can have one guy holding off a horde while the rest of the group feels useful for a bit.
That's taking my "or you could try this" and making it my main point. Let's try being concrete. Suppose you're playing Pathfinder and one of your players has pulled the trigger on Awesome Display. With a jacked Charisma, their Colour Sprays are going to be knocking a lot of encounters over for quite some time. Now, you could deal with this by spamming Undead and Constructs, but what does that achieve other than telling the Oracle player, "I hate your decision and I am going to punish you for it!" Where's the player agency? Instead of punitive measures, the DM can roll with it. Encounters geared towards swarms of weak melee creatures that the Oracle can knock off in twos and threes while the rest of the party is dispatching them in ones and twos lets everyone have fun.

Beat them at their own game.

...

Hoping people don't derail a thread that so far is mostly full of good advice and normal discussion.

Joystealers will knock him down a peg.

That has been my experience with powergamers. But I don't care if someone is powergaming or not, I only care about the harm they do by having a character that is significantly more powerful than the rest of the party.

I've found a few things that can help:
- Some systems attract more powergamers than others.
- Some systems give less reward to powergaming than others. Meaning powergamers cause less problems.
- If there are mechanics that seem to reward power gamers by making planning your build more necessary in order to get a powerful character (eg, aptitudes in DH2), I houserule them out if possible. This makes it easier for everyone to get powerful characters, reducing the gap between powergamers and everyone else.
- I tell my players that every time they take any advance on their character, they have to be able to justify why their character would want training in that thing. I'm not sure if this does anything to stop the powergamer, but it does make them to think a bit more about their characters personality and roleplaying. Plus, I've never said no to any advance a player wants based on this rule, I've seen my players change their minds on a few things that they couldn't justify. Even for things that I wouldn't even ask the player justify to me.
- I put in less (but not 0) challenges that the powergamers PC is good at and more that the other PCs are good at. Evening out how much time each PC has in the spotlight does make things better for the non-powergaming PCs.

If the rest of the party is played by girls, I leave everything as is, the powergamer will keep the party alive while they focus on their pretty outfits and adorable familiars. Male players not duplicating a role covered by the powergamer are also fine.

If any other players are guys duplicating a role the powergamer seems to be covering, I take them aside and tell them their character just stepped on a b.s. trap. When they protest, I admit it's a ruse to cover an opportunity to let them make another character- one that can cover meaningful roles the powergamer isn't covering. If they refuse, I let them lie in the bed they made. If they accept, I guard their new role by interfering with the powergamer's ability to cover that role.

If the powergamer already covers all roles, I take him aside and tell him his character stepped on a b.s. trap. When he protests, I explain that the other players need a role and ask him to give up a role of his choosing, because he was clever- he earned it. He doesn't necessarily have to give up the power, because the other character could go down. I'm just asking him to defer to that player in those situations. If he doesn't follow through, then oh no, looks like he stepped on another trap, this one being deadly...

dude, its simple, ramp up the encounters, b8 their weaknesses, create narrative importance, etc.