I finally made it to host my first session of DnD. We had a lot of fun and no one appeared to be one of all these kinds of problem players I read here about every now and then. All had fun and told me they were satisfied by the way I made the story as DM, so that we just in the same evening took out our agendas to find a date to continue.

That's well so far. But I'm a bit worried about a behavior the players had.

They were describing the world themselves.

For example, when they were looking for cover to hide, when they expected an assault. They told me they are taking cover between the trees to their right side of the path. But they didn't ask me if there are any trees nor did I mention any trees, actually I wasn't even expecting there to be any trees. But as there also was nothing like an assault upcoming I just dropped my version of the area and proceeded with theirs.

This happened a few times1, and I let them go, except one time, when their description was contradicting with something coming up later what they were not aware of yet. That time I told them when they said "We are going to the temple of ... in the city" I told them "But there is no temple of ... in the city" And the players appeared pretty disappointed to me.

So when we ended the session with a long rest, I told them they spotted a small cave on a lawn which provides cover from behind so a perfect spot to make a camp for a long rest. They started preparing what they had to do, and just wanted to fill their waterskins and fill a pot so they can cook a meal. So they needed water and just discussed with each other (not even including me, the DM into the discussion) the best way to get it is taking it from the stream next to the lawn. So I told them, I allow them to make it this time. But the next time they are going to say "We do x with y which is just right here" instead of asking me "Is there some y around, so we can do x with it?" I'll deny it on principle. Again they appeared disappointed to me.


So I'm asking, is it appropriate to disallow this?

On the one hand they obviously had a lot of fun in creating this world together in their imagination. And as long it isn't contradicting with any events of adventure there is no reason for not letting do them so (expect if I keep it that way, they will earlier or later be able to assume to be on an important point for the adventure when ever I deny them to change the world as they want it). But on the other hand I (as DM) felt kind of excluded from the game when the players started describing the world to them selves.

So should I just let them go on with describing them the world to them self, as long it isn't contradicting with the adventure? since the players seemed not to like it the 2 times I told them the place actually looks different to what they assume.

Or is the DM under any circumstance expected to be the descriptive part, and in case I'm assuming correct and they don't like that, DnD might not be the correct game?

noteExcept one person (who played just one time before some years ago) we all played for the first time a pen and paper RPG, if this information is useful for something.

1funny was, they expected arrows sticking in dead horses to be poisoned and handled them all time that way. When they captured a goblin and interrogated him about the kind of poison, it made up a funny conversation while the goblin had no idea what poison they are talking about; Since the arrows were not poisoned.

  • \$\begingroup\$ Comments are not for extended discussion; the conversation about opinions on who should make up details during a game and why has been moved to chat. \$\endgroup\$ Commented Apr 4, 2016 at 16:40
  • 1
    \$\begingroup\$ Related: The PC claims to know an NPC they just met, how should I react as the DM? \$\endgroup\$
    – mxyzplk
    Commented Apr 6, 2016 at 1:27
  • \$\begingroup\$ @mxyzplk: while that post seems to produce answers with a similiar context to the answers here (which is just in common at the "do it the way you prefer" which could be apllied to alot other posts aswell), he is asking a quiet different thing. He wants to know how to prevent this behavior. While this post is asking if preventing it is appropiate and if not doing so might generate dificultys in regards to the RAW. So I'm not sseing this as exactly a duplicate, more as jsut related. \$\endgroup\$
    – Zaibis
    Commented Apr 6, 2016 at 7:08
  • \$\begingroup\$ Are they actually creating the world or simply having a different perception of what's not been filled in? People will usually fill in the unstated things with their perception of normal--to someone who comes from a forested area (or a city within a forested area) trees beside the road would be normal, while someone like me (lifelong desert dweller) would not expect them. \$\endgroup\$ Commented Apr 6, 2016 at 22:53
  • \$\begingroup\$ @LorenPechtel: Well for me the one leads to the other. As the basic rules say me (the DM) is responsible for the world, it is them building the world by filling in parts, I just haven't thought to be there by not mentioning to them (and to my self). As I tryed multiple times to explain: I don't see a problem in this as long I can handle to stick to the main plot. But I was worried about it in view to RAW. Since I don't know all facetes of the game yet. And the DMG and basic rules aswell say the DM has to be responsible for the world. I asked here as not knowing this is important or just loose. \$\endgroup\$
    – Zaibis
    Commented Apr 7, 2016 at 9:33

10 Answers 10


It's ok if it's ok with you.
But from your question I'd say you are not 100% cool with it.

D&D, like many RPGs, boils down to a conversation between the DM/GM/Narrator and the player(s).

The DM describes the scenario.
The player describes what his character does.
(Possibly dice are rolled)
The DM describs the results, how the scenario is changed.

This is in the very first pages of the PHB.

Common things that interfere with this, apparently simple, process:

  • Players not letting the DM finish the initial description. Enthusiasm is good, but they need to understand that if you didn't say 'light' they are in the dark.
  • DM planning too much. Be flexible, players won't do what you expect. Be prepared to be surprised.
  • DM planning too little. Free-styling everything is a myth, very very few people can pull that off effectively.

So, back to your question.
No, the players should not be able to materialize a forest just by saying that it's there. That's your job.
Painting an accurate scene with few words is an important DM skill, you will get better at it. If your players hide a lot, anticipate in your description how easy would that be for them to try.
"You are on a road in the forest. The road is wide enough for two carts to proceed side-by-side. If you stay in the middle you are in the open."
"You are on a path used by wild animals in the forest. You can only proceed in a congo line and the last in line cannot see the first because of vegetation.
Lothar, since you are 6'9" wearing full plate, you have disadvantage on pretty much every action that involves movement."

Same players, same forest, very different situation.

Thing are what you say they are.
Do they need a tree stump to tie a rope? Sure.
Do they need a coal mine? Maybe not.
Do they want to grow a forest? One of them better be an high level druid...

  • 12
    \$\begingroup\$ +1 for the opening line. This is a playstyle issue: Some groups encourage players declare setting details on the fly, others allow them to do it but only at certain times, still others completely discourage it as immersion-breaking, some allow players to make suggestions but give the GM the last word... There's advantages and disadvantages to every approach, so each GM and table need to pick something they're comfortable with. \$\endgroup\$
    – GMJoe
    Commented Apr 5, 2016 at 0:34
  • 1
    \$\begingroup\$ Yeah… improvising everything is hard, and harder in a game system that is designed for preparation, but it's not impossible to fully improvise a game. It's my default way of GMing (and that explains my drift over the years to games that work well run that way). You may want to change “a myth” to “hard”, especially since the rest of that sentence does say it's possible. \$\endgroup\$ Commented Apr 7, 2016 at 17:16
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    \$\begingroup\$ About improvising everything, please note that the OP is a new GM. Sure, you have a ton of experience you know what works and what doens't and you know "the rules" by heart. That's fine, I do the same myself. That's not what I mean by "improvising everything". \$\endgroup\$
    – Sent_
    Commented Apr 8, 2016 at 7:36
  • \$\begingroup\$ Also note, some games encourage players to add elements to the world by default - DnD however is not one of those games. \$\endgroup\$
    – Zibbobz
    Commented Jun 1, 2020 at 12:42

TL&DR: So I'm asking, is this appropriate to disallow this?

TL&DR: Yes, it is appropriate to disallow them creating things ex nihilo in the game world.

You are the DM, you run the world. D&D is a cooperative story telling effort; the DM and the players have different roles.

Ultimately, the Dungeon Master is the authority on the campaign and its setting, even if the setting is a published world.(Basic Rules, p.3/ PHB, p. 6)


If your description of the environment lacks a detail that the player is looking for, the standard interaction is that the character takes in the environment and the player asks questions for more detail. "Is there water nearby?" "Do I see a place where I can refill my canteen?" etcetera.

The player is prompting you for more detail about the environment so that he can propose an action or make a choice. One of the limitations of the game is that the players only know, or can only interact with, the world as described and presented by you (DM).

How to Play. (Basic Rules: p. 3)

  1. The DM describes the environment.

  2. The players describe what they want to do. (My note: DM decides whether or not a die roll is required)

  3. The DM narrates the results of the adventurers’ actions.

    There are a number of games that are more chaotic or open ended, wherein the players participate in world building "on the fly" but D&D isn't structured that way.

    If your players are disappointed, you need to sit down with them, with the Basic Rules, the Players Handbook, the DMG, etcetera, and agree on how this game works. It is possible that this game isn't the game they want to play.

The Dungeons & Dragons roleplaying game is about storytelling in worlds of swords and sorcery. (p. 2, Basic Rules).

How do the players fill in the world as part of the ongoing story?

  • By creating their backgrounds and character concepts

  • By asking you questions (sometimes their questions give you new ideas to work with)

  • By their proposals for action (such as asking for more detail about the environment so that they can make choices that you provide on the fly or based on your world concept)
  • By making decisions and taking actions
  • By their interactions with the world (including the NPCs/Monsters in it) that you present.

    Their choices build the story, not the fantasy world itself. The world is your responsibility.

Players contributing to world building can make your DMing job easier

If they want to contribute to world building more deeply, that can also work with the following caveat: you need to retain the rights to say "yeah, that fits, let's go with that" or "no, that doesn't fit this game world, let's try something else."

  • Example 1: My brother's 5e game world is a bit over two years old at this point. He had a minimal pantheon laid out for us to pick from (for those who wanted a deity). I chose to play a Cleric (Life Domain). I proposed additional deity for his pantheon: the god of Brewing and Beer. The proposed deity, and his portfolio, were attached to an email to my brother. He made a couple of modifications, noted how the deity was related to his existent pantheon, and presto: I had contributed to the game world in a way that fit his scheme. He could have said "nah, doesn't fit" and I'd have been fine with that.
  • Example 2: Names on the fly. I do this a lot in three different campaigns I've been in. I've had a knack for making up names for years, so sometimes we'll meet an NPC. One of the other players will ask for the NPC's name and the DM will have (obviously) not come up with a name yet. It takes me a second, or two max, to make up a name, sometimes humorous and sometimes straight laced, and I'll propose it. Most DM's don't mind when I do that. The one who does? Has to make up his own names. :) One of the silly ones I offered up a few months back was a gnome prisoner whom we freed. Once we had freed him form the orcs who had captured him, our wizard asked him his name. My brother paused, and I piped in

    "I think he's named Izov ... Izov Bleu. He's got blue eyes, right?"

    My brother had described him being bound and gagged, and his blue eyes looking at the rogue with a pleading expression when he was found tied up in the basement of a tower. After the whole table groaned, my brother picked up on the improv and replied "Why yes, I'm surprised that you've heard of me."

    At some tables, contributions like that work, and at other ones they may not. Work it out at the table and see what's fun for your group.

  • 4
    \$\begingroup\$ +1 for talking to the group. There's clearly a mismatch in assumptions going on \$\endgroup\$ Commented Apr 4, 2016 at 15:16
  • 3
    \$\begingroup\$ +1 for pointing out that players asking about the presence or absence of details helps the GM fill out their descriptions of places in a constructive way. \$\endgroup\$
    – GMJoe
    Commented Apr 5, 2016 at 0:36
  • 5
    \$\begingroup\$ You might also want to precise that players' question should be more "open-ended" and focused on their intentions to avoid the X/Y problem. Imagine that A wants to fill her flask with water, she may ask "Is there a stream?" and there may not be one, however if she asks "Is there a way I can fill my flask with water?", she may learn there is a well close by. The DM cannot divine that the player asks for a stream to re-supply her water (she may ask for fishing, washing up, ...), and therefore may not make the connection with the well. \$\endgroup\$ Commented Apr 5, 2016 at 17:48
  • \$\begingroup\$ @MatthieuM. Ok, I tried to make that clearer. \$\endgroup\$ Commented Apr 5, 2016 at 17:54

From the very beginning of the DMG:

The DM creates a world for the other players to explore,[...] As a storyteller, the DM helps the other players visualize what's happening around them...

One of the roles of the DM is to describe what PCs see (or, more generally, perceive). This is an important aspect of your role and it has to be clarified from the very beginning of the game. I suspect that this point was not clear to the players. Also, it is possible that your description of the environment was a bit fleeting, thus leaving a lot of space for imagination.

If you don't like how your players added information to your world, remember to describe things in such a way that this problem is unlikely to happen, that is, describe everything that you consider to be relevant. For example, if you say you are walking along a path without trees or other coverage on its sides, the situation you described before would not happen. Obviously, it could happen that the players are interested in something you did not mention. In this case, it has to be clear to the players that they must first ask you if that thing is present, and then proceed.


The assumption of D&D are that the DM describes the world, and the Players describe their character's actions in it.

A side effect of this is that it leads to "DM may I"; in order to generate interesting actions (say, grabbing a banner, using it to swing to the other side of the staircase, knocking the gnolls down), instead of saying what your character tries to do you first have to "vet" your idea with the DM.

"Are there banners or anything hanging? Does it look like I could swing from them? Does it look like they will hold my weight? Can I reach the other side of the staircase by swinging on them?"

In comparison:

"I grab a banner hanging on the staircase, and swing out over the void, then kick into the gnolls on the far side."

The first is a Q&A for any interesting environmental interacting action, or extremely detailed environmental descriptions (including the load-bearing capacity of any banners!)

"DM may I" is one of the reasons why spellcasters are often considered a better option than non-spellcasters outside of any "balance" criteria: Spellcasters have snippets of rules text that they can use to impose their own narrative on the game world. They don't have to ask "is there something I can light on fire with my torch", they just cast fireball or burning hands. They don't ask if there is cover so they can make a stealth check, they cast invisibility. They don't have to ask the DM if there is anything useful they can use in the world, they change the world with in-game rules.

If you go with giving the players the ability to narrate details of their surroundings during actions, characters who are not spell casters can have more opportunity to impose their own narrative on the game. Which can lead to a better story.


It's up to you but...

Allowing players to build the world makes the game easier

By letting the players assume there was a tree immediately accessible, they were allowed to make the encounter easier. This probably isn't that big of a deal, but if they become accustomed to it, they will get better at finding what they need at just the right time.

Ask yourself how you will react if the players assume there's a rope they can cut to a chandelier immediately above the villain, dropping it on their head. If this is unpalatable to you, you need to set expectations as soon as possible. Encourage your players to ask questions to learn more about the scene. Since your players are resisting this kind of thing, try to say "yes" as much as possible, at least while they're getting accustomed. If you say "yes" to the trees, they'll (hopefully) be more willing to accept "no" for the chandelier.

As you practice DMing, you will also get better at anticipating questions the players might ask. Since hiding behind trees is a pretty common response to enemies in the forest, write down how dense the vegetation is before the session. The more you explain upfront (within reason), the less opportunities your players will have to be frustrated.

All of this is assuming that your players want to be challenged by limitations. They may instead prefer a collaborative storytelling session that's more about creativity than challenging encounters. If this is the case, you will probably need to have a talk with your players and decide if that's something you're willing to try.


It is often a process of give and take

The classic roles of GM and player are, as noted in this answer, to describe the world and to act in the world. This is what the rules-as-written support in the D&D genre.

I often see two broad classes of failure mode:

1. Improper assumptions

Simply put, it is not possible to completely and in detail describe everything that the players are sensing at all times. Assumptions are made on both ends: The GM assumes some default knowledge, information, and conventions about pushing details to the players; and the players do the same about pulling or interpreting information from the GM.

So a common failure mode that could lead to what you're describing is that when you describe a path through (say) "the wilderness" you may be envisioning treeless Kansas prairie while your players are picturing Pacific Northwest forests. They are not so much creating detail (intentionally) as exploiting features of the area they (incorrectly) inferred from a description.

What you do about that is up to you, but it may not be the same thing in all situations. Do the existence of trees at the side of the path bother you as a GM? It might-- you might have deliberately tried to evoke a Kansas prairie or similar treeless environment for a reason. Maybe it's for the campaign setting, maybe trees were cleared away for some upcoming plot point, maybe you just had a battle in mind with no cover available. If some reason like this obtains, it is perfectly legitimate to back the players up and clarify the setting.

In fact, even if some reason like this does not obtain, you're still justified in doing it. The only question is whether you gain more than you lose by doing it, and that depends on your group dynamics.

These issues tend to sort themselves out after a few sessions, and maybe having a quick discussion, GM-to-players: The GM and players will (or should) both naturally learn about the assumptions that the others are making, and start tailoring descriptions and questions to minimize confusion in the future.

2. Role Confusion

But another failure mode is when the GM and the players have genuine disagreements over who controls the world and setting, how much, and to what degree. There are some games (my personal experience is with text/e-mail games, but there are many face to face gaming examples) where the players are accorded more power than the GM=world, players=characters method I described above.

These issues, I find, do not tend to naturally sort themselves out. They are sort-able, but they usually require a lengthier discussion about who has what role, who has control over the environment (and in what situations) and how conflicts are resolved.

It is, to my mind, still entirely justified (especially in a D&D game which, which supports the classic GM/player separation) to bring the players to the table and (politely!) tell them how it's going to be.

3. Your situation

I cannot quite tell from your description if you're having one of these issues, or both of these issues. The trees vs no-trees seems like a fairly benign instance of the "improper assumptions" problem, unless you had gone out of your way to emphasize a treeless environment. Trees vs no trees are both reasonable interpretations if a description is somewhat generic and does not emphasize the matter one way or the other.

The other two examples... those might be going the other way into some role confusion.


It's best to give your players freedom

What you've described sounds great. You should be really pleased that the players are applying this kind of free reasoning to the game. It shows your players are engaged with the game and willing to think freely about engaging with the game world. The key is to let them contribute reasonable features of the game world whilst not losing control of the game. It sounds to me like you're doing this pretty well.

My advice: loosen up. Nothing is going wrong; in fact, it's going really well. Make sure you stick to your guns if their invention goes against an established fact or a forthcoming event but otherwise enjoy the benefits of their creativity.


When players help to narrate the world in this manner, many DMs see it as a sign of engagement -- it means the players are having fun and the game is going well. Players are happy when they are able to do things and sad when they can't, so it's good when players can narrate minor details to let them do things better.

Here's a concrete example. The party was in a cave, and a player turned to me and asked: "How high is the ceiling?" Caught off guard, I answered: "Uh, it's ten feet high I guess." The player answered: "Drat! That means I can't wild shape into my larger combat forms, because none of them would fit in the corridor!" I hadn't meant to block that player from participating in combat, and I felt really bad that I had done so accidentally, but I didn't see a good way to reverse my ruling. I wished the player had simply said: "I wild-shape into my huge combat form" and not asked if the ceiling was high enough.

Having said that, obviously there are some things you can't allow the players to narrate. For example if they're trying to get into a locked building, and a player says: "I walk around back and let myself in through the unlocked back door, and then I open the front so you guys can get in", you'd have to respond by telling them there is no back door -- otherwise it would break the scene.

So I guess my answer is: in general you should allow the players to help build the world, unless it breaks an important piece of your plot.

PS. You wrote about the players finding arrows stuck in some dead horses, and assuming the arrows were poisoned. If you think this would be a fun development, the right thing to do is to change reality to match their expectations: agree with them that the arrows are poisoned, and make up something weird about the poison for them to learn about!


Definitions and References

What you are struggling with is the concept of "narrative control." In the beginning of RPGs, coming from wargames, there was an assumption that the GM had complete autocratic control over everything but the characters, and the players had domain only over their characters' reactions and thoughts and (attempted) actions.

However, since this wasn't RAW but was an undocumented assumption, various modes of play began to emerge even within D&D. This turned into a much larger movement where there are many games today that share narrative control between the players and the GM. See: What is a “shared narrative” RPG?

It can be hard for players and GMs weaned on the traditional model to "get" shared narrative play. See: Spoilt for choice: helping traditional-system players adapt to narrative-control games

In fact, your question is probably a duplicate of The PC claims to know an NPC they just met, how should I react as the DM? which struggles with the same question for 5e. Many players have played newer games and come to D&D with the playstyles and assumptions from those and not the old D&D/wargame roots assumptions. In general D&D has tried to not be too prescriptive on the subject, as it fills the role of the "big tent" RPG that people can use for fantasy/horror/mystery, in a simulationist/gamist/narrativist way, in infinite settings, with many houserules.

What To Do?

"Can" you shut down your players and reserve all narrative control for yourself? Yes, sure. You're the GM and thus the ultimate authority in the game (in D&D 5e and other trad games).

Should you? Possibly not. Let me explain how I evolved my GMing from GM-control to shared-narrative in D&D and related games. I started with Star Frontiers and D&D Basic back in the early '80's. So my games all had those old assumptions of GM narrative control - it didn't occur to me or any of my fellow gamers that there was another option.

Then in the mid-'90s I ran the game Feng Shui by Robin Laws, a cinematic action RPG. It's not a full modern indie shared narrative game, but it does exactly what your players are doing. I sum up its aesthetic thus: "If there's a fight in a pizza parlor and someone says 'I pick up a pizza cutter and slash the guy across the face' - sure, great! If they say 'I come up from behind the counter with a missile launcher' you call BS. Stop wasting game time on 'Mother may I' questions; players shouldn't ask how far away the helicopter skid is they should just try to jump to it."

This was fun in Feng Shui and revolutionized how I ran D&D. D&D, frequently, is an exercise to cram 15 minutes of actual fun into a 4 hour play session. Every bit of "is there a branch around big enough for me to pick up and use as a weapon? Is there a chandelier I can swing from?" "Oh I don't know, let me think, pore over the room description, maybe roll a die..." It's waste. Pure dross that is taking up time that could be instead occupied with activity and fun. Allowing players to do simple things without playing 20 questions and giving them some input into the game world increases their investment and fun.

But Then Isn't There Chaos?

No. At least, not in my experience. It's easy to be scared of shared narration but many of the negative attributes you see in games (min-maxers, trolls, etc.) are actually being exacerbated by the lack of shared control (and thus shared responsibility) for the fun of the group by the players.

You will want to set the parameters of control. Maybe it's just "hide in the bushes" level, and things like poisoned arrows you take under advisement but don't let players say. Or you might let them declare things - often this is controlled in games like FATE by spending some kind of game currency (hint: Inspiration). Discuss this with your group. You're still the GM, so if you feel like someone's cheeseweaseling it or coming up with lame stuff or countermanding your plots (though in some games, you just let the players come up with the plots too - welcome to lazy GMing!) you can always draw the line. (And/or let the other players - in the totally GM-less game Committee for the Exploration of Mysteries you just let the other players declare something one player said sounds lame and skip it...)

Anyway, it's fine to decide you don't want to share narrative control, but you probably need to educate yourself on it and try it before making that decision - it's a valid playstyle, including for D&D 5e, and has a lot of advantages.


Technically, but Why Bother?

There are actually many games that rely on players providing details without the GM prompting them to do so. Powered by the Apocalypse (specifically, Dungeon World) comes to mind as the most relevant example, but lots of other games certainly benefit from it.

However, there is a difference between adding details to a scene and contravening existing details. In your example, you describe the players walking down a path and then they add the idea that the path is lined with trees. This is an example of "Yes, and..." improvisation and it generally works rather well to make the narrative more interesting. Had you described a flat, open plain for miles in all directions and the players mentioned ducking into the nearby forest this would have been an example of "Yes, but..." improvisation. This is sometimes necessary, especially for the DM, but can be much jarring because it requires taking a step back from the story to resolve the changes it creates to the existing narrative.

"Yes, and..." improvisation is not without its problem, although you as the DM can take steps to mitigate them. The two major ones that occur to me are:

Sometimes players try to add detail that the setting doesn't allow for.

This can best be mitigated by creating expectations about the setting for the players. A little narrative prologue to a session or scene can be a good way to establish such expectations as it relates to things that will be happening. However, when this fails you need to use a "Yes, but..." but try to avoid saying "No" if you can do so without breaking the setting or narrative.

Sometimes players add details that accidentally break the GM's planned solution.

The best way to avoid this problem is by planning the obstacles instead of the solutions. You should make sure that you can think of at least one solution so that you can hand it to the players as needed but part of the fun in RPGs is being creative. If you restrict the solutions to a problem, you are taking away from that.

If, for some reason, the nature of your obstacle relies on certain things being true or false, make sure you include your details in the description.

An Example

DM: You are following the thin mountain trail when you a come to a point where a rock-slide has apparently knocked away part of trail leaving only a sliver of a ledge on which to stand. Looking down you can see a fall would result in serious injury. What do you do?

Yes, and...

Player: I grab my grappling hook and try to hook it around the tree branch overhead. Makes appropriate roll. Alright, I swing across.

DM: The branch creaks as your weight settles on it, snapping at the far end of your swing. Roll to grab onto something before you fall.

Yes, but...

Player: It looks like someone has come this way before and left a rope for folks to hold onto.

DM: Okay, give me a second... alright. Sure, they left a rope here but it must have been during the winter, shortly after the rock slide. The spring rains seem to have caused the rope to start rotting. Do you want to chance using it?


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